three of four numbers have a sum of 22. if the average of the four numbers is 8, what is the fourth number?

Mathematics

2 answers:

Murrr4er [49]3 years ago

7 0

Let the unknown number be x.
as the average of the four numbers is 8
⇒ (22 + x)/4 = 8
⇒22 + x = 32
⇒x = 10

MakcuM [25]3 years ago

4 0

The 4th number is 10, since you need to add 10 to get 32 so that when you divide by 4 you get 8

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7 0

3 years ago

Angles A and B are complementary and in ratio of 3:6. What is the measure of each angle

pashok25 [27]

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$\bf \cfrac{A}{B}=\cfrac{3}{6}\implies \cfrac{A}{B}=\cfrac{1}{2}\implies 2A=\boxed{B}
\\\\[-0.35em]
~\dotfill\\\\
A+B=90\implies A+\boxed{2A}=90\implies 3A=90\\\\\\ A=\cfrac{90}{3}\implies \blacktriangleright A=30 \blacktriangleleft
\\\\[-0.35em]
\rule{34em}{0.25pt}\\\\
2(30)=B\implies \blacktriangleright 60=B \blacktriangleleft$