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a) $29
b) $112.50

Let x = initial amount of money.

After buying the watch, Jennifer has (2/3)x.
After mother, Jennifer has (2/3)
x + 12.
After buying the dress, Jennifer has (2/3)( (2/3)x + 12) = (4/9)x+8
Thus, (4/9)
x+8 = 58, so x = 112.5

Going back to the beginning, with $112.50 as the initial amount. After the watch, Jennifer has $75. Mom gives her $12, so she has $87. The dress is (1/3) this amount, or $29.

Yes, I totally agree.

This post has received a 0.78 % upvote from @speedvoter thanks to: @larryphang.

Ans of a) $37.5
Ans of a) $112.5

Ans of a) $37.5
Ans of b) $112.5

You got a 0.82% upvote from @mercurybot courtesy of @larryphang!

a) 29
b) 112.5