Answer:
F = 668.9N
Step-by-step explanation:
Using the formula;
m1d1 = m2d2
m1 and m2 are the masses
d1 and d2 are the distances
Substitute;
15 * 2.5 = x * (55/100) [55cm was converted to metres]
37.5 = 0.55x
Swap
0.55x = 37.5
x = 37.5/0.55
x = 68.18kg
Since F = mg
F = 68.18 * 9.81
F = 668.9N
This gives the required force