"the cost of a phone is reduced by 20%. the new cost is $70.40. what was the original price? " plz

This question is incomplete. Here is the complete question:

The cost of a phone is reduced by 20%. The new cost is $70.40 . What was the original price?

1. $88.00

2.$84.00

3.$58.40

4.$56.00

The correct answer is option 1. $ 88.

Step-by-step explanation:

Let's analyze the information we have:

We know that the cost of the product was reduced by 20%, leaving $ 70.4 as the final price.

As we do not know what the original cost of the product is, we will assign an x.

Now, we know that 20% is the reduced cost, so we can logically say that what is left represents the remaining 80%, that is, the $ 70.40.

So, now we will do a cross-multiplication:

If 80% 70.40

   100% --- x

80x = 70.40. 100

80x = 7040

X = 7040: 80

X = 88

This way we can verify that the correct option is $ 88

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6

make sure you have version 2.50

try looking in the very back of the book : )

step-by-step explanation:

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