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3 years ago

The difference in age between Brita and her daughter Eva is 30 years. The sum or their ages 118. How old is Eva?

Mathematics

1 answer:

Alona [7]3 years ago

3 0

Answer:

Eva's age is 44 years

Step-by-step explanation:

Let

x ----> Brita's age

y ----> Eva's age

we know that

The sum or their ages 118

$x+y=118$ ----> equation A

The difference in age between Brita and her daughter Eva is 30 years

$x-y=30$ ----> equation B

Solve the system by elimination

Adds equation A and equation B

$x+y=118\\x-y=30\\---------\\x+x=118+30\\2x=148\\x=74$

Find the value of y

substitute the value of x in any equation

$74+y=118\\y=118-74\\y=44$

therefore

Eva's age is 44 years

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Answer:

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Step-by-step explanation:

Consider the provided information.

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Find the z score

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