Answer:
121/9
Step-by-step explanation:
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Let x= original savings
(x-1,600) - 2/5 (x-1,600) = 1/3x
(x-1,600) - 2/5 + 640 = 1/3x
(3/5)x - 960 = 1/3x
(3/5)x - (1/3)x = 960
(4/15)x = 960
(15/4)(4/15)x = (15/4) 960
x = 15* 240 (960/4 = 240)
x = $3,600 is his original savings
Check:
$3,600 - 1,600 = 2,000
(2/5)($2,000) = $800
2,000 - 800 = 1,200 left over
C is a function. X cannot repeat itself more than once, that will make it not a function. For example 1,1, 1,2, 1,3 x repeats itself 3 times that is NOT a function. Y can repeat itself more than once but X cannot.
