y varies directly as the square of R. If y is 7 when R is 3, find y when R is 15 . a) Write the variation. b) Find y when R is 15.

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Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

Name each raycalculation tip: in ray "ab", a is the endpoint of the ray.