Answer:
18 weeks
Step-by-step explanation:
830-200=630 then you do 630/35=18
Roberto overtakes Juanita at the rate of (7.7 mi)/(11 h) = 0.7 mi/h. This is the difference in their speeds. The sum of their speeds is (7.7 mi)/1 h) = 7.7 mi/h.
Roberto walks at the rate (7.7 + 0.7)/2 = 4.2 mi/h.
Juanita walks at the rate 4.2 - 0.7 = 3.5 mi/h.
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In a "sum and diference" problem, one solution is half the total of the sum and difference. If we let R and J be the respective speeds of Roberto and Juanita, we have
R + J = total speed
R - J = difference speed
Adding these two equations, we have
2R = (total speed + difference speed)
R = (total speed + difference speed)2 . . . . . as computed above
The number is (20 x 19 x 18 x 17) / (4 x 3 x 2). That's 4,845 . None of the choices is correct.
You have to put the circle among the circumstances
So, all you would do is use distribution.
For example: D is .5(x+3) = -3(x-.5)
you would do
.5 times x+3, which equals .5x+ 1.5
So, .5x+1.5=-3x+1.5
because -3*x-.5 is -3x+1.5.
Then, you would just get x by itself.
.5x+1.5=-3x+1.5
add 3 over to .5 = 3.5x;
subtract 1.5 over to 1.5 = 0
now you have 3.5x = 0
divide by 3.5 to get x by itself and you get zero.
x=0
When you substitute it in, you should have them both equal to each other. I hope this helps. :)
