A triangle is 180°. So you can do:
3.2n + 6.4n + 2.4n = 180 Simplify
12n = 180
n = 15 Now that you know the value of n, you can plug it into each individual angle/equation
∠X = 3.2n plug in 15 for n
∠X = 3.2(15)
∠X = 48°
∠Y = 6.4(15)
∠Y = 96°
∠Z = 2.4(15)
∠Z = 36°
1/9 = 1.11
29/8 = 3.63
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3.73 = 269/72
or....
1/9 >>> 8/72 (72 is the common denominator) (Multiply the N and D by 8)
29/8 >>> 261/72 (72 is the common denominator) (Multiply the N and D by 9)
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269/72
The answer for that is .. 17?