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3 years ago

A cake that costs $32 is on sale for 15% off and there are no taxes. Explain why the expression

Mathematics

1 answer:

Darya [45]3 years ago

7 0

Answer:

$27.2

Step-by-step explanation:

A cake that costs $32 is on sale for 15% off and there are no taxes. Explain why the expression (0.85).32 represents the final price of the cake in dollars.

This is explained in the calculation below

= A cake that costs $32 is on sale for 15% off

The amount off the cake is calculated as

= 15% of $32

= 15/100 × 32

= $4.8

The amount he is paying for the cake =>$32 - $4.8

= $27.2

The above expression is obtained as

(0.85).32

= (100% - 15%) × 32

=( 1 - 0.15) × 32

= 0.85 × 32

= $27.2

The final price of the cake = $27.2

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Let the price of a piece of jewelry is $x and that of a piece of hair accessories is $y.

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3 years ago

There were 800 math instructors at a mathematics convention. Forty instructors were randomly selected and given an IQ test. The

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Answer:

95% confidence interval for the mean of the 800 instructors is [126.80 , 133.20].

Step-by-step explanation:

We are given that there were 800 math instructors at a mathematics convention.

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where, $\bar X$ = sample mean score = 130

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= [ $130-2.0225 \times {\frac{10}{\sqrt{40} } }$ , $130+2.0225 \times {\frac{10}{\sqrt{40} } }$ ]

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