Q. If x and y are in direct proportion and y is 2 when x is 8 , find y when x is 12 .Answer: y=
Establish Equation: Establish the direct variation equation.Since x and y are in direct proportion, we can write the relationship as y=kx, where k is the constant of proportionality.
Find Constant of Proportionality: Use the given values to find the constant of proportionality k. We know that y=2 when x=8. Substitute these values into the equation to find k. 2=k×8
Solve for k: Solve for k.Divide both sides of the equation by 8 to isolate k.k = rac{2}{8}k = rac{1}{4}
Write Equation with k: Write the direct variation equation with the found value of k. Now that we have k=41, the direct variation equation is y=(41)x.
Find y for x=12: Find y when x is 12.Substitute x=12 into the direct variation equation y=41x.y=41×12y=3
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