12x2= $24
24 + 28 + 45 = $97
Thus, $97 represents the total amount (100%)
Calculating 100% - 30% gives 70% (with 30% discount)
(noting that 70% equals 70/100 or 0.7)
Therefore, 97 x 0.7 = $67.90
It seems you are stating that Y=4/X+SQRT X +0.2 -5X, with x given as 4/5. To compute <span>Y=4/X+SQRT X +0.2 -5X, substitute every instance of x with 4/5:
y = 4 / (4/5) + sqrt(4/5) + 0.2 - 5(4/5)
= 5 + 2 / sqrt(5) + 0.2 - 4.
Can this expression be further simplified?
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