Lets look at the info we have:-
6 friends
Pay $90 and receive $42 in change.
Question:-
How much does each friend pay?
To answer this first we nee to find out how much they paed in total. lets do that 1st:-
90 - 42 = 48
They paid $48 for the gift.
CHECK OUR WORK:-
48 + 42 = 90
We were RIGHT!!
Now lets divide to find out how much each person paid:-
48 ÷ 6 = 8
Each friend pays $8.
CHECK OUR WORK:-
8 × 6 = 48
We were RIGHT!!
So, each friend pays $8 for the gift.
Hope I helped ya!! xD