So the total amount of marbles is: 20+12=32
there are 20 pink marbles
20/32 = 10/16 = 5/8 (simplified)
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
If the number is between 25 and 35 It would have to be either 28 or 32.
Step-by-step explanation:
A = P*e*r*t
P = 1,000
e = 2.71828
r = 0.09
t = 1
A = (1,000)*(2.71828)*(0.09)*(1)
A = 244.65
