120 ÷ ( 3 + 5 ) = 120 ÷ 8 = 15
15 × 3 = 45
15 × 5 = 75
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Answer:
15:75
Step-by-step explanation:
120 = 3x plus 5x
120 = 8x
120/8 = x
x = 15
3*15 = 45 and 5*15 = 75
