Answer:
D
Step-by-step explanation:
Given y varies directly as x and z then the equation relating them is
y = kxz ← k is the constant of variation
To find k use the condition y = 
when x = 1 and z = 4 , then
= k × 1 × 4 = 4k ( divide both sides by 4 )
= k
y = xz ← equation of variation
When x = 6 and z = 3 , then
y = × 6 × 3 = × 18 = 2 × 6 = 12
All of them.
1. If you multiply by 2, they will be equal.
2. If you multiply by 5000 they will be equal.
3. If you divide by 3 they will be equal.
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