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
Two ratios form a proportion if they are equal. If one fraction is equivalent to the other fraction, they form a proportion. To find out, reduce both fractions and see if they are equal.
A
1/2 and 4/2
Reduce 4/2 to 2/1.
1/2 and 2/1 are not equal.
1/2 and 4/2 do not form a proportion.
B
2/1 and 4/8
Reduce 4/8 to 1/2.
2/1 and 1/2 are not equal.
2/1 and 4/8 do not form a proportion
C
1/2 and 8/4
Reduce 8/4 to 2/1.
1/2 and 2/1 are not equal.
1/2 and 8/4 do not form a proportion
D
2/1 and 16/8
Reduce 16/8 to 2/1
2/1 and 2/1 are equal.
2/1 and 16/8 form a proportion.
Answer: D. 2/1 and 16/8
FALSE! Any 3 angles of any triangle add up to 180 degrees. An equilateral triangle's angles should each be 60 degrees.
Answer:
Jacey has 48 rocks. Carter has 6 rocks.
If Carter and Jacey are the only factor owners of 54 rocks
We divide 48 by 8 = 6 rocks: 42 difference;
Which is also 54 as 6 + 48 = 54
They now have 48 difference
6,6, 6,6, 6,6, 6,6 = 48
We see 48 - 6 = 42.
We also see 48 + 6 = 54
54=6 = 48
48 difference is the denominating divider; meaning 48/8 = 6 is how we first find the answer before adding on the 6 to show the difference of 8 equal shares.