use rates, the rate a person is working is the reciprocal of the time
working together, they work at a rate of 1/3 job per hour
when two people work together their rates add together
---> 1/h + 1/j = 1/3
---> h = j - 8 (harry takes 8 hrs less than jimmy)
substitute and solve for j
<span><span>1<span>j−8</span></span>+<span>1j</span>=<span>13</span></span>
combine fractions
<span><span><span>j+(j−8)</span><span>j(j−8)</span></span>=<span>13</span></span>
cross-multiply
<span><span>j2</span>−8j=6j−24</span>
<span><span>j2</span>−14j+24=0</span>
Factor
<span>(j−12)(j−2)=0</span>
j = 12
It takes jimmy 12 hours to rake the leaves
Answer:
e) 20
Step-by-step explanation:
Segment lengths:
|(2, 7) -> (8, 7)| = |(8-2, 7-7)| = |(6, 0)| = 6
|(8, 7) -? (8, 11)| = |(8-8, 11-7)| = |(0, 4)| = 4
because we know it's a rectangle, we can infer that the other two sides also have lengths 4 and 6, so the perimeter is 4+4+6+6=20
Answer:
-122.5
Step-by-step explanation:
Difference = 7 - 4 = 3 terms; 8.75 - (-70) = 78.75
1 term → 78.75/3 = 26.25
therefore, u2 = - 70 - 2(26.25) = -122.5
Topic: Patterns + Common difference
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After five weeks they will have the same amount of money.
