If a:b = 2:1 and b:c = 3:1, then what are a:c and a:b:c?
2025
If a:b = 2:1 and b:c = 3:1, then what are a:c and a:b:c?
- A.
a:c = 6:1; a:b:c = 6:3:1
- B.
a:c = 1:4; a:b:c = 1:3:4
- C.
a:c = 3:2; a:b:c = 3:2:1
- D.
a:c = 2:3; a:b:c = 2:1:3
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Correct answer: A
Given: a:b = 2:1 and b:c = 3:1.
Make the common term b equal in both ratios.
In a:b = 2:1, b is 1. Multiply both parts by 3 to make b = 3, so a:b = 6:3.
Now combine a:b = 6:3 with b:c = 3:1 to get a:b:c = 6:3:1.
From a:b:c = 6:3:1, the ratio a:c is 6:1.
Correct answer: a:c = 6:1 and a:b:c = 6:3:1.