Q. If y varies inversely as x, and y=10 when x=4, what is the value of y when x=8 ?A) y=2.5B) y=5C) y=40D) y=51
Given Inverse Variation: Given that y varies inversely as x. This means y=xk where k is a constant.
Find Constant k: We know y=10 when x=4. Substitute these values to find k. 10=4k.
Write Variation Equation: Solve for k: Multiply both sides by 4 to isolate k. 10×4=k. k=40.
Find y for x=8: Now, use the found value of k to write the inverse variation equation. y=x40.
Find y for x=8: Now, use the found value of k to write the inverse variation equation. y=x40. To find y when x=8, substitute 8 for x in the equation. y=840. y=5.
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