First computer takes x min. For 1 min it does 1/x part of work.

Second computer takes (x+24) min. For one min it does 1/(x+24) part of work.

Both computers for one min do (1/x+1/(x+24)) part of work.

At the same time, both computers for one min do 1/9 part of work.

$\frac{1}{x} + \frac{1}{x+24} = \frac{1}{9} 
\\ \\ \frac{x+24+x}{x(x+24)} = \frac{1}{9} 
\\ \\9(2x+24)=x^{2} +24x
\\ \\ 18x+216=x^{2} +24x
\\ \\ x^{2}+6x-216=0
\\ \\ D=b^{2}-4ac=36+4*216 = 900
\\ \\ x= \frac{-b+/- \sqrt{D} }{2a} = \frac{-6+/-30}{2} 
\\ \\ x_{1}=-18, x_{2}=12

We can use only positive number here. So, 

for the first computer x=12 min,

 for second computer x+24=12+24= 36 min

Answer 12 min and 36 min.$

7 0

3 years ago

What is the probability of drawing two yellow marbles if the first one is NOT placed back into the bag before the second draw? T

Xelga [282]

Break it down into two parts. First, what is the probability of drawing a blue marble on the first draw?Since there are 5 blue marbles and 10 total, the probability is 5⁄10, or 1/2. Now since we no longer have that blue marble, there are 4 blue marbles and 9 total. The chances of drawing a blue marble are 4/9. Therefore, the chance that both marbles drawn are blue is the chance that the first one is blue times the chance that the second one is blue. 1/2 * 4/9 = 4/18 = 2/9 Remember, math is always trying to trick you. It wants you to try and do the whole big problem at once, which can be difficult. Break it down into smaller problems, then use your answers to small parts to find the answer to the big question.

Ishrat

6 0

3 years ago

Read 2 more answers

How many different combination of numbers can you make from 7 numbers?

jekas [21]

It would be 36 to the 7 power = 36’7. Hope this helps!

3 0

3 years ago