Let x represent the amount of money that Victoria had before she went for shopping.
Victoria spent one-fourth or her birthday money on clothes. It means that the amount she spent on shopping is 1/4 × x = x/4. Amount that she was having left would be x - x/4 = 3x/4
She received another 25$ a week later. The amount that she is having at this point will be 3x/4 + 25
Using Pythagoras’ theorem a2 + b2 = c2 you can find out the third (longest) side. (6x6) + (8x8) = 100 (the square root of 100 is 10) so ur final sum is 6+8+10 = 24 mm