Here's how to do dividing in a certain ratio:
-- You want to divide up the whole thing in the ratio of
4 parts, 5 parts, and 9 parts.
-- How many parts all together ? (4 + 5 + 9) = 18 parts all together.
-- The whole thing is 180, and that's 18 total parts.
So each part is (180/18) = 10 degrees.
4 parts = (4 x 10) = 40
5 parts = (5 x 10) = 50
9 parts = (9 x 10) = 90.
Check: (40 + 50 + 90) = 180 . yay!
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For the second one, I think there are some words missing.
<span>n = fraction 5 over 3
Explanation;
</span>

<span>Eliminate the demominator by multiplying each term by 5.
3n-4=1
3n=5
n=</span>
Answer:
Pierre has enough boards and nails to make 9 tables and 5 chairs.
Step-by-step explanation:
13T+8C ≤ 220
Let us substitute 9 for T and 5 for C and check.
13(9) + 8(5) = 117 + 40
= 157 < 220
So, 220 wooden boards are sufficient to make 9 tables and 5 chairs.
48T+37C ≤ 760
Substitute 9 for T and 5 for C.
48(9)+37(5) = 432 + 185
= 617 < 760
So, 760 nails are sufficient to make 9 tables and 5 chairs.
Hence, Pierre has enough boards and nails to make 9 tables and 5 chairs.
Answer:
D. 
Step-by-step explanation:

To rewrite a mixed number as an improper fraction, first, multiply the whole number by the denominator.

Then, add this number to the numerator.

This number is now the numerator of the fraction. The denominator stays the same.

I hope this helps!