"Women as a group will admit we are probably less sophisticated financially than men," said the lady from Master Charge headquarters in New York. "But that is changing."

It is changing, in part, because the spending habits of women now are on record.

The Equal Opportunity Credit Act, which passed in 1975 and has been phasing in gradually since, has made credit lines more available for women and, along the way, has allowed more women to build up credit histories of their own.

As of last month, the act expanded to require that banks, on request, keep separate credit histories for a husband and wife. Master Charge card applications from now on will include a place to indicate whether two credit histories are desired. Persons who already have cards will have to request the change.

"In case a couple should split up, this will make it easier for both of them to keep their credit," said Sandra Powers, the consumer affairs adviser for Master Charge. Powers was in Washington recently as part of an informational tour about the new credit laws.

No one can say - not officially at least - how many more women today are applying for and using credit cards; banks are not supposed to be keeping such records.

Powers said to take it on faith that "many more women are applying in their own name for charge cards." This, she added, is not only a reflection of less discriminating credit standards, but also a function of demographics.

For instance, the U.S. divorce rate is now one out of three couples. One out of eight households are headed by a woman. And women comprise 40 per cent of the U.S. work force.

Powers said only three factors should go into a financial institution's decision to grant credit: income, stability and credit history. If a person suspects the institution has received false information, he or she can requests a copy of his or her credit record under the Fair Credit Act.

Different institutions use different methods for weighting each factor. It's no secret that credit is easier to come by in some parts of the country than in others, Powers said.

Sometimes a person doesn't even have to travel to a different part of the country, but just walk down the block to get a better hearing. "Shop around. Banks are competitive," Powers advises persons denied credit at one bank or dissatisfied with the credit service being given.

One area in which banks don't compete, however, is the interest they charge. That is set state by state, and in most states the maximum rate allowed is 18 per cent. Powers said she doesn't know a bank that charges anything less than the maximum - even among the ones who are finding Master Charge a very profitable business.

"There are a lot of support acitvities that go into sustaining the operation." Powers said, justifying the rates, "Also, the credit card allows the consumer to walk around and decide" - she snaps her fingers - "instantly he's going to give himself a loan. It's a tremendous convenience and that costs something."

Despite the high interest rates, Master Charge and other credit cards have been gaining in popularity. The number of Master Charge cardholders in the U.S. increased by 3.7 million to a record level of 40.7 million in 1976, an increase of nearly 10 per cent over the previous year. Sales on the card in the U.S. rose by $2.4 billion to a record $13.7 billion, an increase of 21 per cent over 1975.

More thanone-third of the population in Maryland holds a Master Charge card. In Virginia, the card-holders number more than a million.