Use the geometric sequence formula to solve for rate:
an=a1r^(n-1)
6.75=4.5r^(2-1)
6.75=4.5r
6.75/4.5=r
r= 1.5
and if you want to make sure just multiply each number by 1.5 and see if it gets you the next number
4.5 4.5×1.5=6.75 (holds true)
6.75 6.75×1.5=10.125 (holds true)
10.125 10.125×1.5=15.1875 (holds true)
15.1875
1.5 is the multiplicatice rate hope that helps :)
Answer:
together rate = 1/20 min/job
one comp. rate = 1/(x-9) min/job
2nd comp. rate = 1/x min/job
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Equation:
rate + rate = together rate
1/x + 1/(x-9) = 1/20
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20(x-9) + 20x = x(x-9)
40x-9*20 = x^2-9x
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x^2-49x + 180 = 0
Factor:
(x-45)(x-4) = 0
Realistic solution since 4-9 is negative:
x = 45 minutes
then
x-9 = 36 minutes (faster computer time to do the job)
Step-by-step explanation:
Answer:
It is C -14r+6p
Step-by-step explanation:
If you want the explanation just tell me
After 6 hours the amount of caffeine 40 mg. After another 6 hours the amount of caffeine is 20 mg. It takes 12 hours for the total amount of caffeine to drop down to 20 mg. the answer is 11 am -B. Hope this helps!