<span>44 tens is the same as
440 </span>
We can solve this problem by stating that the summation
of momentums must be zero. That is, the momentum at one end of the pivot must
be equal to the momentum at the other end.
Momentum 1 = Momentum 2
Since Momentum is the product of Force and Distance, and
with this rule created, we can say that:
F1 * d1 = F2 * d2
Where,
F1 = 60 lbs
d1 = 2 inches from the pivot
F2 = unknown X
d2 = 3 inches from the pivot
Substituting to the equation to find for F2:
60 lbs * 2 inches = F2 * 3 inches
F2 = 40 lbs
<span>Therefore 40 lbs of upward force must be pushed to open
the valve.</span>
<span>Answer: B</span>
OK, so this is assuming we are considering that the first three kids to solve ARE NOT in the first day.
So we have 3 kids and it doubles
Day 1 : 6
Day 2 : 12
Day 3 : 24
Day 4 : 48
Day 5 : 96
Day 6 : 192
Day 7: 384
So it should take 7 days or a week to solve all the problems.
The equation:
(3 * 2)^x = 384