Answer:
80.
Step-by-step explanation:
When multiplying if the tenth place is " 7" then we look " next door" which is the ones and 8 is great then 5 so we count to from 8 to see when the next number ending in 0 would be in this case its 80. ( if the number is 4 or less count backwards to a number ending with 0 which in that case would have been 70 ) but the answer is 80.
Answer:
The first increase was of 60%.
Step-by-step explanation:
The initial value of the product is x.
The first increase was of y.
The second increase is of 25%, that is, 1.25.
The final price was double the original, so 2x.
This situation can be modeled by the following equation:

We want to find y.
Simplifying by x



After the first increase, the value was 1.6 of the original value, that is a increase as a percent of (1.6 - 1)*100 = 60%.
Answer:
8 packages.
Step-by-step explanation:
6.25 x 8 = 50 bucks.
He can also buy 2 packages of muffins.
Hope I helped.
Answer:
The rocket's maximum height will be 1424 feet.
It will reach that height in 4 seconds.
It will reach the ground in 8 seconds.
Step-by-step explanation:
One easy way to find the peak is to find the derivative and solve for zero:
h(t) = -16t² + 128t + 1680
To find the derivative of each term in that format, you simply multiply the coefficient by the exponent, and reduce the exponent by one. In the case of terms with no variable, they disappear. That gives us:
h'(t) = -32t + 128
This derivative describes the rate of change of h with respect to t, so to find the peak, we simply need to solve it for zero:
0 = -32t + 128
32t = 128
t = 4
So the maximum height occurs when t = 4. Let's plug it in to the original equation:
h(t) = -16t² + 128t + 1680
h(4) = -256 + 512 + 1680
h(4) = 1424
So the rocket's maxiumum height is 1424 feet.
And we've already answered the second question, it happens at 4 seconds.
Also, the amount of time going up will be the same as the amount of time going down, which means that it will reach the ground in twice that time, or 8 seconds.
-1,3 that’s easy u should definitely pay attention in class