Gabby's and Tina's savings were in the ratio of 4 : 9. Both of them shared the cost of their mother's present equally. Gabby's remaining savings was ²₅ as much as Tina's savings. What percentage of her savings did Gabby spend? Correct the answer to 1 decimal place.

	Gabby	Tina	Difference
Before	4x3 = 12 u	9x3 = 27 u	5x3 = 15 u
Change	- 2 u	- 2 u
After	2x5 = 10 u	5x5 = 25 u	3x5 = 15 u

Since Gabby and Tina shared the cost of their mother's present equally, the amount each paid for the present is the same. 

So, the difference in the amounts between Gabby and Tina at first and in the end remains the same.  Make the difference in the amounts between Gabby and Tina at first and in the end the same. LCM of 5 and 3 is 15.

Amount that Gabby spent on the present
= 12 u - 10 u
= 2 u

Percentage of her savings that Gabby spent
= ²₁₂ x 100%
≈ 16.7%

Answer(s): 16.7%