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Inessa [10]
3 years ago
12

John is twice as old as Mary. The sum of their ages is 21. How old is Mary?

Mathematics
2 answers:
Mazyrski [523]3 years ago
6 0

Answer:

Mary is 7

Step-by-step explanation:

If their ages combined equals 21 and john is twice Mary’s age then johns age takes up 2/3 of 21. that would b 14. 14 is 2 x 7. and Mary is 7. 14+7=21. Mary is 7 years old

inn [45]3 years ago
4 0

Correct answers are:

J + M = 21

J - 2M = 0

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