If Y varies directly with x....

[InNeedOfHelp!]

A pitcher has given up 12 runs in 20 innings. If it is assumed that the number of runs varies directly as the number of innings, how many runs would be given up in 9 innings?

As I understand it, when you have an XY variation, you multiply x1 by y1 or x2 by y2 to come up with the result. However, multiplying 12 by 9 comes up with 108, which seems quite impossible. Can ya help?

 

[Denis]

A pitcher has given up 12 runs in 20 innings. If it is assumed that the number of runs varies directly as the number of innings, how many runs would be given up in 9 innings?
As I understand it, when you have an XY variation, you multiply x1 by y1 or x2 by y2 to come up with the result. However, multiplying 12 by 9 comes up with 108, which seems quite impossible. Can ya help?

r = runs

r / 9 = 12 / 20
20r = 108

finish it?

 

[stapel]

A pitcher has given up 12 runs in 20 innings. If it is assumed that the number of runs varies directly as the number of innings, how many runs would be given up in 9 innings?

Variation statements translate as follows:

. . . . ."y varies directly as x": y = kx

. . . . ."y varies inversely as x": y = k/x

. . . . ."y varies jointly with x and z": y = kxz

So plug your given initial values into the appropriate formula, and solve for the variation constant "k". Then rewrite the formula with this value for "k", and evaluate at the listed value, solving for the answer.

Eliz.