Answer:
a) 72.25sec
b) 6.25secs
c) after 10.5secs and 2 secs
Step-by-step explanation:
Given the height reached by the rocket expressed as;
s(t)= -4t^2 + 50t - 84
At maximum height, the velocity of the rocket is zero i.e ds/dt = 0
ds/dt = -8t + 50
0 = -8t + 50
8t = 50
t = 50/8
t = 6.25secs
Hence it will reach the maximum height after 6.25secs
To get the maximum height, you will substitute t - 6.25s into the given expression
s(t)= -4t^2 + 50t - 84
s(6.25) = -4(6.25)^2 + 50(6.25) - 84
s(6.25) = -156.25 + 312.5 - 84
s(6.25) = 72.25feet
Hence the maximum height reached by the rocket is 72.25feet
The rocket will reach the ground when s(t) = 0
Substitute into the expression
s(t)= -4t^2 + 50t - 84
0 = -4t^2 + 50t - 84
4t^2 - 50t + 84 = 0
2t^2 - 25t + 42 = 0
2t^2 - 4t - 21t + 42 = 0
2t(t-2)-21(t-2) = 0
(2t - 21) (t - 2) = 0
2t - 21 = 0 and t - 2 = 0
2t = 21 and t = 2
t = 10.5 and 2
Hence the time the rocket will reach the ground are after 10.5secs and 2 secs
This question belongs to greatest common factor.
49 = 7*7
56 = 7*8
So Greatest common factor = 7
Hence Susan can arrange 7 mugs on one shelf.
For 49 blue mugs, Susan can arrange 7 mugs in 7 shelves.
For 56 red mugs, Susan can arrange 7 mugs on 8 shelves.
Hence, 7 shelves are needed for BLUE mugs and 8 shelves are needed for RED mugs.
Answer:
60 miles per hour
Step-by-step explanation:
For each point just divide the miles by the hour
120/2 = 60 mph
180/3 = 60 mph
240/4 = 60 mph
Answer:
Step-by-step explanation:
Total Weight of the package = weight of product + weight of box
Weight of empty box =0.88lb
Total weight of the box is =7.24lb
Let Weight of product inside box=w
Let wet of empty box =y
Total weight = F
Then,
F=y+w
Since F=7.24lb. y=0.88
Then, w=F-y
w=7.24-0.88
w=6.36lb
The weight of the product is 6.36lb
