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10 votes
Ayden earned a grade of 89% on his multiple choice history final that had a total of

200 problems. How many problems on the final exam did Ayden answer correctly?

User Bitloner
by
3.8k points

2 Answers

4 votes

Answer:

178

Explanation:

just trust meee

User Raymus
by
4.1k points
11 votes

Answer:

178

Explanation:

Method 1: Set up a proportion

Set up an equation of the form:

\frac{\color{red}{\text{part}}}{\color{orange}{\text{whole}}}=

whole

part

=

\,\,\frac{\color{blue}{\text{percent}}}{100}

100

percent

Assign the variable xx to the unknown value:

\color{red}{x}=

x=

\,\,\color{red}{\text{part}}

part

The question asks what \textit{part}part of the total questions is 89%

Substitute the known values with the numbers given in the problem, and the unknown value with xx:

\frac{\color{red}{x}}{\color{orange}{200}}=

200

x

=

\,\,\frac{\color{blue}{89}}{100}

100

89

Solve for xx:

100\cdot\color{red}{x}=

100⋅x=

\,\,\color{orange}{200}\cdot\color{blue}{89}

200⋅89

Cross multiply

\frac{100x}{100}=

100

100x

=

\,\,\frac{17800}{100}

100

17800

Divide both sides by 100

178

Simplify

Method 2: Convert to decimal and multiply

{89}{100}=0.89

89%=

100

89

=0.89

Move decimal 2 places to the left

{Multiply result by the total:}

Multiply result by the total:

0.89{200}=

0.89⋅200=

178

number

percent

178

89%

200

100%

User Echiban
by
5.0k points