Question

The sale price of an item is four-fifths the original price of the item, x.

Which statement explains why both 45x and 0.8x can find the sale price of the item?



A. The expressions are not equivalent.

B. Multiplying by 45 is the same as multiplying by 80%.

C. Multiplying by 54 is the same as multiplying by 0.8.

D. The fraction 45 is the same as the decimal 0.2. Therefore, 45x can be written as 0.2x.

Answer 1

B. Multiplying by 45 is the same as multiplying by 80%.

Answer 2

B. Multiplying by
`(4)/(5)` is the same as multiplying by 80%.

Explanation:

Let x be the original price of item.

We have been given that the sale price of an item is four-fifths the original price of the item.

Let us find the sale price of item.

`\text{Sale price}=(4)/(5)x`

`\text{Sale price}=0.8x`

Let us convert 0.8 into percentage by multiplying by 100%.

`\text{Sale price}=(0.8)(100\%)x`

`\text{Sale price}=(80\%)x`

Therefore, the sale price of the item could be figured out by
`(4)/(5)x` and
`0.8x` because Multiplying by
`(4)/(5)` is the same as multiplying by 80%.