Answer:
900
Step-by-step explanation:
The ratio of the number of people who own a smartphone to the number of people who a flip phone is 5:3.
Let the number of people who own a flip phone=x
If 600 more people own a smartphone than a flip phone, then the number of people who own a smartphone=x+600
To find x, we express the ratio and population as an equality.
5:3=x+600:x
Expressing the ratios as fractions would give:

Next, we cross multiply
5x=3(x+600)
Open the brackets by expansion.
5x=3x+(3 X 600)
5x=3x+1800
Subtract 3x from both sides.
5x-3x=3x-3x+1800
2x=1800
Divide both sides by 2
x=900.
Since x=900, the number of people who own a flip phone is 900.
S(r) = 2pi*r*h + 2pi*r^2
S ' (r) = 2pi*h + 2*2*pi*r .... differentiate with respect to r
S ' (r) = 2pi*h + 4pi*r
S ' (3) = 2pi*h + 4pi*3 ... plug in r = 3
S ' (3) = 2pi*h + 12pi
S ' (3) = 2pi*2 + 12pi .... plug in h = 2
S ' (3) = 4pi + 12pi
S ' (3) = 16pi
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Answer: D) 16pi
Answer:
25%
Step-by-step explanation:
Given data
original quantity =12
new quantity =15
% increase= new-original/original *100
% increase= 15-12/12 *100
% increase= 3/12 *100
% increase=0.25 *100
% increase=25%
hence the increase is 25%.
Answer:
Step-by-step explanation:
It c just took the test