HOOKE'S LAW : The distance d when a spring is stretched by a hanging object

varies directly as the weight w of the object. The distance is 62 cm when the weight is 4kg, what is the distance when the weight is 9 kg?
Please help, this one is killing me.
Thanks a mill!!

d is proportional to w

hence d=kw where k is the constant of proportionality

as the law is for all weights

d1=kw1......1)
d2=kw2.......2)


dividing 1) by 2)


d1/d2=w1/w2



where d1= 62 cm
d2 is the distance you want to find
w1= 4 kg
w2=9kg



hence we have

d2 =( w2 * d1)/w1
d2 = (9 * 62)/4
d2= 139.5 cm

note that i didnt convert 62cm to Metres and hence my ans is in cm.

Feel free to covert!

d = k w
62 = 4 k
k = 31/2

d = (31/2) 9 cm
d = 139.5 kg