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3 years ago

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Twice a number is decreased by 9, and this sum is multiplied by 4. The result is 8 less than 10 times the number. What is the nu

mber?

1 answer:

Sati [7]3 years ago

7 0

4(2n - 9) = 10n - 8

8n - 36 = 10n - 8

8n - 8n - 36 = 10n - 8n - 8

-36 = 2n - 8

-36 + 8 = 2n - 8 + 8

-28 = 2n

-28/2 = 2n/2

-14 = n

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