# Banknotes

Eva deposit 7800 USD in 50 banknotes in the bank.
They had value 100 USD and 200 USD.
How many were they?

Result

a =  22
b =  28

#### Solution:

a+b = 50
100a+200b = 7800

a+b = 50
100a+200b = 7800

a = 22
b = 28

Calculated by our linear equations calculator.

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