The distance d when a spring is stretched by a hanging object varies directly as the weight w of the object. If the distance is 39 cm when the weight is 4 kg, what is the distance when the weight is 7 kg?
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Since the distance that the spring is stretched varies directly as the weight of the object, we have:
d = kw, for some constant k.
Then, given that d = 39 when w = 4:
39 = 4k ==> k = 39/4.
Thus, the equation that relates d and w is:
d = (39/4)w.
Therefore, when w = 7:
d = (39/4)(7) = 68.25 cm.
I hope this helps!
d = kw, for some constant k.
Then, given that d = 39 when w = 4:
39 = 4k ==> k = 39/4.
Thus, the equation that relates d and w is:
d = (39/4)w.
Therefore, when w = 7:
d = (39/4)(7) = 68.25 cm.
I hope this helps!
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d = kw, where d is the distance stretched and w is the weight.
d = 39 cm when w = 4 kg, so k=39/4 cm/kg
When w=7kg, d=(39/4)(7) cm = 68.25 cm
d = 39 cm when w = 4 kg, so k=39/4 cm/kg
When w=7kg, d=(39/4)(7) cm = 68.25 cm