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Pls help me!

Mr. Chen writes the expression 4 × (7 − 2)^2÷ 10 on the board. Keisha said the first step is to evaluate the exponent 2^2 . Explain Keisha's mistake, and then evaluate the expression.

Pls help me! Mr. Chen writes the expression 4 × (7 − 2)^2÷ 10 on the board. Keisha-example-1
User Jaynetics
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2 Answers

5 votes

Answer:

Explanation:

According to BODMAS, we have to first evalute the expression inside the bracket.
Therefore, 4(7 -2)^2 ÷ 10
= 4(5)^2÷ 10
=4(25)/10
=4(2.5)
=10

User Iordanis
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7.3k points
4 votes

Answer:

Keisha's mistake was identifying the exponent in the expression as 2^2, which is not correct. The exponent in the expression is actually (7-2)^2, which means we must first subtract 2 from 7, and then square the result.

So, (7-2)^2 = 5^2 = 25.

Next, we must multiply 4 by 25, giving us 100.

Finally, we divide 100 by 10, resulting in 10.

Therefore, the value of the expression is 10.

User Jyjek
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7.4k points