BobPursley has 3 more brothers than sisters, how many more brothers than sisters does his sister mary have?
If the family has b boys and g girls,
b = g+4
So, b = (g-1)+5
so, each sister has 5 more brothers than sisters
To find out how many more brothers than sisters Mary, BobPursley's sister, has, we need to know the number of brothers and sisters BobPursley has.
Let's assume that BobPursley has x sisters. Since BobPursley has 3 more brothers than sisters, he has x + 3 brothers.
Now, let's find out how many more brothers than sisters Mary has. Mary is also one of BobPursley's sisters, so she has the same number of brothers and sisters as BobPursley.
Therefore, Mary has x sisters and x + 3 brothers.
To find out how many more brothers than sisters Mary has, we subtract the number of sisters from the number of brothers:
(x + 3) - x = 3
So, Mary has 3 more brothers than sisters.