For the given problem
Let one bath towel costs x
And one hand towel cost y
Helen bought 4 bath towels and 3 hand towels for $72
so,
Althea bought 3 bath towels and 6 hand towels of the same kind for $84
So,
Solve the equations (1) and (2) to find x and y
Multiply equation (1) by (-2) then add to equation (2) to cross y
then solve for x
Substitute with x into equation (1) to find y
So, the answer will be:
The cost of one bath towel = $12
The cost of one hand towel = $8