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3 years ago

14

Janice is thinking of two numbers. She says that two times the first number plus the second number is 41. In addition, the firs

t number plus three times the second number is 73. Find the numbers

1 answer:

Rudiy273 years ago

7 0

Let one of the number be x and the other be y

<span>two times the first number plus the second number is 41
</span>2x + y = 41

<span>the first number plus three times the second number is 73
x + 3y = 73

</span>2x + y = 41 --------- (1)
x + 3y = 73 --------- (2)

From (1):
2x + y = 41
y = 41 - 2x ------- sub into (2)
x + 3(41-2x) = 73
x + 123 - 6x = 73
x -6x = 73 - 123
-5x = -50
x = 10 -------- sub into (1)
2 (10) + y = 41
20 + y = 41
y = 41 - 20
y = 21

Ans: x = 10, y = 21

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- - -

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