Question 1209504
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Another bizarre and incorrect AI solution from that pseudo-tutor....<br>
"Since they had the same amount of money left, the fractions of money they spent must be equal"<br>
That makes no logical sense.  And, besides, the statement of the problem tells us the fractions of their money that each spent, and they are not equal.<br>
Following is a logical and correct solution from a human tutor....<br>
Let J and G respectively represent the amounts of money Jamie and Grace started with.<br>
Let x be the cost of each diary; then the cost of each book was x+$3.30.<br>
Jamie spent 3/4 of her money, so she finished with 1/4 of what she started with.<br>  Grace spent 5/9 of her money, so she finished with 4/9 of what she started with.<br>
They finished with the same amounts of money:<br>
[1] {{{(1/4)J=(4/9)G}}}<br>
Jamie spent 3/4 of her money on 3 books:<br>
[2] {{{(3/4)J=3(x+3.30)}}}<br>
Grace spent 5/9 of her money on 2 diaries:<br>
[3] {{{(5/9)G=2(x)}}}<br>
The amount of money Jamie had left was {{{(1/4)/(3/4)=1/3}}} of what she spent:<br>
[4] {{{(1/3)(3(x+3.30))=x+3.30}}}<br>
The amount of money Grace had left was {{{(4/9)/(5/9)=4/5}}} of what she spent:<br>
[5] {{{(4/5)(2(x))=(8/5)x}}}<br>
The amounts they ended up with were the same:<br>
[6] {{{x+3.30=(8/5)x}}}
{{{3.30=(3/5)x}}}
{{{x=5.50}}}<br>
The cost of each diary was x=$5.50; the cost of each book was x+$3.30 = $8.80.<br>
Jamie ended up with x+$3.30 = $8.80; that was 1/4 of what she started with, so she started with 4($8.80) = $35.20.<br>
Grace ended up with was (8/5)x = $8.80; that was 4/9 of what she started with, so she started with (9/4)($8.80) = 9($2.20) = $19.80.<br>
The total the two of them started with together was $35.20+$19.80 = $55.<br>
ANSWER: $55<br>
Summary....
Jamie started with $35.20 and spent 3/4 of it ($26.40) on 3 books costing $8.80 each, finishing with 1/4 of $35.20, or $8.80.
Grace started with $19.80 and spent 5/9 of it ($11.00) on 2 diaries costing $5.50 each, finishing with 4/9 of $19.80, or $8.80.
The two of them finished with equal amounts.<br>