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3 years ago

John is twice as old as Mary. The sum of their ages is 52. How old is Mary?

Mathematics

2 answers:

Salsk061 [2.6K]3 years ago

4 0

John =2M
M= M
So M+2M=52

2nd choice

tatuchka [14]3 years ago

3 0

Answer:

J = 2M and J + M = 52

Step-by-step explanation:

Let John's age be J

Let Mary's age be M

Now we are given that John is twice as old as Mary

So, John's age = $J = 2M$

Now we are given that The sum of their ages is 52.

So, $J+M=52$

Thus the system of equations could be used to solve the problem is $J = 2M$ and $J+M=52$

Hence Option B is correct.

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3 years ago

A man that is 6 feet tall casts a shadow 5 feet long. At the same time, a lamppost beside the man casts a shadow 25 feet long. H

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Data

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3 years ago

Help? a) 2/10 + 8/100 b) 13/100 + 4/10 c) 6/10 + 39/100 D) 70/100 + 3/10

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$\green{––––––––––––––––––––––––––––––}$

$\huge\red{\boxed{\tt{{«ANSWER»}}}}$

A) 2/10 + 8/100 = 0.28
B) 13/100 + 4/10 = 0.53
C) 6/10 + 39/100 = 0.99
D) 70/100 + 3/10 = 1

 $\green{––––––––––––––––––––––––––––––}$ 

#carry on learning <3

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2 years ago

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Answer:

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