Answer:
-24.8 m/s
Step-by-step explanation:
Given:
y₀ = 60 m
y = 40 m
v₀ = 15 m/s
a = -9.8 m/s²
Find: v
There are three constant acceleration equations we can use:
y = y₀ + v₀ t + ½ at²
v = at + v₀
v² = v₀² + 2a(y − y₀)
We aren't given the time, so we need to use the third equation, which is independent of time:
v² = v₀² + 2a(y − y₀)
Plug in the values:
v² = (15 m/s)² + 2(-9.8 m/s²) (40 m − 60 m)
v² = 617 m²/s²
v ≈ ±24.8 m/s
Since the coin is on the way down, the velocity is negative. So v = -24.8 m/s.
Answer:
5 months
Step-by-step explanation:
Equate the formulas for the weights of the two boys:
J's weight = 120 lb + (10 lb/mo)m = D's weight = 150 lb + (4 lb/mo)m
Solve as follows: Subtract 120 lb from both sides:
(10 lb/mo)m = 30 lb + (4 lb/mo)m.
Then: (6 lb/mo)m = 30 lb, and m = (30 lb) / (6 lb/mo) = 5 months
It doesn't give the entire question, Do they want to know how many pieces were in the total cake? If so, I think it would be 384. You subtract the 3 pieces that Mindy ate and that leaves 96 that Tony had which was supposed to be 1/4 of the cake. Dividing the cake into 4 sections of 96 and multiplying would give you 384.
If they want to know how many slices of cake were left after Tony ate the fourth (96 slices), it would be 288
