The picture of and accompanying prices for General Electric light bulbs in the story about food prices last week was incorrect. The light bulbs that had been priced were standard bulbs, not soft white. The correct prices for the standard bulbs at Plus and both Giants is 4/$1.49. CAPTION: Picture 1, (TABLE)(NEW-LINE) *2*COMSTOCK CHERRY(NEW-LINE) *2*PIE FILLING (NEW-LINE)PLUS(COLUMN)$1.29(NEW-LINE)GIANT (Vienna)(COLUMN)$1.29(NEW-LINE)GIANT (McLean)(COLUMN)$1.49(END TABLE);Picture 2,(TABLE)(NEW-LINE) *2*CHEEZ WIZ (NEW-LINE)PLUS(COLUMN)$1.59(NEW-LINE)GIANT (Vienna)(COLUMN)$2.33(NEW-LINE)Giant (McLean)(COLUMN)$2.33(END TABLE);Picture 3,(TABLE)(NEW-LINE) *2*TIDE 84 OZ. BOX (NEW-LINE)PLUS(COLUMN)$2.49(NEW-LINE)GIANT (Vienna)(COLUMN)$2.49(NEW-LINE)GIANT (McLean)(COLUMN)$2.69(END TABLE);Picture 4,(TABLE)(NEW-LINE) *2*VELVETTA CHEESE(NEW-LINE) *2*32 OZ. PACKAGE (NEW-LINE)Plus(COLUMN)$2.69(NEW-LINE)GIANT (Vienna)(COLUMN)$2.69(NEW-LINE)GIANT (McLean)(COLUMN)$3.85(END TABLE);Picture 5,(TABLE)(NEW-LINE) *2*WELCH'S GRAPE JELLY(NEW-LINE) *2*20 OZ. JAR (NEW-LINE)PLUS(COLUMN)$.69(NEW-LINE)GIANT (Vienna)(COLUMN)$.69(NEW-LINE)GIANT (McLean)(COLUMN)$1.09(END TABLE);Picture 6,(TABLE)(NEW-LINE) *2*(4) 60-75 WATT GE(NEW-LINE) *2*LIGHT BULBS (NEW-LINE)PLUS(COLUMN)$1.00(NEW-LINE)GIANT (Vienna)(COLUMN)$1.49(NEW-LINE)GIANT (McLean)(COLUMN)$1.49(END TABLE)

RECENTLY I have discovered something very interesting and unadvertised:" wrote a Virginia woman. "Giant has different prices on the same items in different stores. This can be as much as 30 cents difference on one item. When I asked the manager about this, I was told that Giant stores close to the new PLUS stores have to be more competitive."

The new Plus stores, subsidiaries of A&P, to which the shopper refers, are part of a recent phenomenon in this country known as the no-frills or limited assortment stores where prices are lower than those found in the conventional supermarket.

In light of an almost industry-wide practice of one-price policy in a given zone, and complaints in the past that inner city stores charge more than suburban stores, the Virginia woman's letter was more than enough to send a reporter out to do some checking.

A story in an industry trade paper offered added impetus. According to Supermarket News: "Giant, which for a few months has focused on how responsive food shoppers are to wider merchandise selection and additional services, also has met prices of A&P Plus Stores at about 12 of its outlets close to the limited assortment units, according to local trade sources. 'Giant has maintained its image of meeting all competition . . .' an observer said."

Both the Virginia shopper and the trade paper were right about lower prices at a Giant store located near a Plus store according to a 200-item price survey conducted by The Washington Post Food Section Jan. 9 in Vienna, Va. Whether or not Giant is maintaining an image of "meeting all the competition," is not so easily determined.

But Giant's claim in a Nov. 1 ad that even with all its services "it costs no more to shop at Giant," was not borne out. While the Vienna Giant and Plus stores had 50 items that were the same price, the total bill for the market basket (which was reduced to 177 items by the time the items which were not available in all locations had been eliminated) at the Plus store was $177.91 and at its Giant neighbor was $197.17.

a few miles down the road, at a McLean, Va., Giant a price check bore out the writer's contention. The same 177-item market basket cost $219.47. Only 20 items were the same price at Plus and both Giants. When sharp cheddar cheese costs $2.19 a pound at Plus, $2.65 a pound at the Giant across the street and $2.75 a pound at the McLean Giant, it's easy to see how the spread can be so large.

Asked to explain the different pricing structure, Giant spokesman Barry Scher said: "We have a one-price pollicy. I am surprised to hear this. Let me call you back."

When Scher called back he reiterated Giant's one-price policy philosophy. "However," he added, " on occasion, due to marketing conditions, we may experiment with a different pricing program and that's what we are doing in a very small number of Giant stores and only on a very small number of grocery items."

Asked if the stores, "less than 10 percent of the total chain," or under 12, were chosen on the basis of their proximity to the Plus stores and other no-frills operations, Scher said, "That's just one consideration for this experimental program.

"No merchant is going to sit back and lose customers and you do what you can to make it grow.

"The idea of any program," Scher said, "is to see if you can increase sales volume, to see if you can expand it." But Scher could not say how long it will take before Giant determines if the program is successful enough to expand. Industry sources indicate that Giant has actually begun to raise the prices on a number of items it had priced competitively with neighboring Plus stores. How many prices Giant cut to meet Plus prices is open to debate: figures range from 250 to 1,000 items.

Safeway has not engaged in head-to-head competition with Plus stores. The chain says it made its price cuts over the entire division on about 165 items. Approximately 161 of the 177 items were price checked at Safeway and the other three stores. The total Safeway market basket was $209.95; at Plus $162.45; at the lower-priced Giant, $179.45 and at the McLean Giant, $199.89.

In most Washington market basket surveys, the price difference between Safeway and Giant is usually a matter of pennies. According to Safeway spokesman Ernie Moore: "A survey of approximately 160 items is only about 1 percent of the total number of items we normally carry in our store. On any given week we will have different prices than our competition, some lower, some higher, depending on new costs, warehouse delivery dates, our merchandising plan and specials."

Because of The Post's price survey Safeway conducted its own, Moore said. They used "those 35 items used by food editors in their annual national survey. "We believe," Moore said, "this market basket is more meaningful in that it better represents what our customers are buying on a regular basis."

The survey, Moore said, showed that Safeway was $1.18 lower than Giant.

For Washington area shoppers all this activity, which began slowly last year with the opening of the area's first no-frills store, Bag 'N Box in Takoma Park, is good news. The arrival of six Plus stores, all of them in the suburbs, appears to have stimulated some competition. Yesterday, another no-frills store, Save More Foods, opened in the District. According to Supermarket News, the Plus stores in the Washington-Baltimore areas have been the most successful. ". . . the most disappointing results had been in New York and New Jersey -- two of the most heavily competitive markets in the country." Washington is considered one of the least competitive with Giant and Safeway sharing 70 percent of the market.

Shoppers in the Vienna Plus store were so pleased with the prices, several came up to a reporter to offer unsolicited comments. "Boy," said one. "I hope you stick it to the other stores so this one can stay in business. I like the idea of competition."

Another said she shopped at Plus, which has been open since September, and Magruders. "I'm satisfied with most of the house brands," which she said were "about the same" as the house brands at one of the area's large chains. "I think you save quite a bit, but when I go up to Long Island I try to shop there because it's cheaper."

"Since this place opened," said another shopper, "I have a new routine. I come here and buy whatever I can. Then I go to a regular supermarket for the rest of the things."

Several shoppers said they saved between 15 and 20 percent on their groceries, more than 50 percent of which are private label goods.

In exchange for these savings, "up to 30 percent lower" Plus offers fewer amenities. They stock only about 1,000 items, sell no fresh meat, fish or poultry and just a few fruits and vegetables. They do not cash checks or take coupons, have no games or displays, charge 3 cents apiece for bags or give you free boxes, sell the products out of the boxes, do no individual price marking and have limited store hours. Often the savings are a matter of pennies; sometimes they are a good deal more.

If you shopped at Plus you would pay 79 cents for 8 ounces of Philadelphia cream cheese, which would cost you 99 cents at the McLean Giant and 95 cents at Safeway. Four 60 or 75 watt GE light bulbs would cost you $1 at Plus and $1.49 at the other stores. Meunster cheese is $1.99 at Plus, $2.59 at both Giants and $2.19 at Safeway. Velveeta cheese in the 32-ounce package is $2.69 at Plus, $3.85 at the McLean Giant and at Safeway. Comstock cherry pie filling is $1.29 at Plus, $1.49 at the McLean Giant and $1.85 at Safeway. House brand reconstituted lemon juice is 56 cents at Plus, 95 cents at McLean Giant and 99 cents at Safeway.

Tide in the 84-ounce box costs $2.49 at Plus, $2.69 at McLean Giant and $3.69 at Safeway. Cheez Wiz is $1.59 at Plus and $2.33 in the other stores. House brand spaghetti is 33 cents a pound at Plus and 59 cents in McLean Giant and Safeway. A 20-ounce jar of Welch's Grape Jelly is 69 cents at Plus and $1.09 at the McLean Giant and at Safeway. House brand pink dish detergent in the 32-ounce container is 43 cents at Plus and 59 cents in the other stores.

House brand white vinegar is 39 cents and 53 cents in the McLean Giant and at Safeway. House brand tomato sauce is 29 cents at Plus and 2/89 at McLean Giant and at Safeway. House brand iodized salt is 16 cents at Plus, 19 cents at the McLean Giant at 29 cents at Safeway. House brand frozen chopped spinach is 26 cents at Plus, 2/67 at McLean Giant and 2/79 at Safeway. Plus nonfat dry milk in a 4-pound box is $4.19 at Plus, $4.39 at McLean Giant and $4.29 at Safeway.

The Virginia shopper who first brought up the question of Giant's two-price policy says it has made shopping even more difficult. "It makes comparison shopping virtually impossible," she said.

Asked why Giant did not place ads in the newspapers advising shoppers of the stores in which prices are lower, Scher said "it was an advertising department's decision. We may have put it in flyers."

According to the president of the Plus stores, Fritz Teelen, "Giant's price cutting didn't have any impact on our operation."

Have the Plus stores cut into Giant's business? Barry Scher was asked.

"I can't answer that. I don't know." sing journalism, or will they see it as the latest plot by the "satanic".