3 years ago

50% of a certain number is 39. What is the number?

1 answer:

8 0

Let that certain number be 'n'

50% (n) = 39

50% ⇒ 0.5

0.5 (n) = 39

Divide both sides by 0.5

0.5n = 39
/0.5 /0.5

n = 78.

So that certain number is actually 78! :)

CROSS CHECK:

50% of 78

0.5 × 78

= 39

Hope this helps! :)

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3 years ago

What does n equal to in 12n + 9 = 6 - 3n

sveticcg [70]

$12n+9=6-3n\ \ \ \ \ \ |Add\ 3n\ to\ each\ side\\\\
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