Answer:
It will take 10 hours.
Step-by-step explanation:
We know distance = rate * time
Sally's rate = 55
Jim's rate = 65
We want Jim to be 100 miles ahead of Sally
The time will always be the same.
d =Sally's distance
Sally
d = 55t
Jim
d+100 = 65 t
We know have 2 equations with 2 unknowns. Substitute d= 55t into Jim's equations
55t + 100 = 65t
Subtract 55t from both sides.
55t-55t + 100 = 65t-55t
100 = 10t
divide each side by 10
100/10 = 10t/10
10 = t
10 - 5 1/8
Convert 5 1/8 into an improper fraction.
We do this by multiplying the denominator to the whole number and adding it to the numerator, and wee keep the denominator.
8 * 5 = 40 + 1 = 41/8
10 - 41/8
Convert 10 to a denominator of 8:
10 * 8 = 80
1 * 8 = 8
80/8 = 41/8
Subtract the numerators together and keep the denominator:
39/8
Convert to a mixed number:
4 7/8
I think there is data that is missing. Please attach the drawing so that to help you
Answers:
bio = 258
sociology = 169
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Work Shown:
x = number of bio textbooks
y = number of sociology textbooks
x+y = 427 books sold total
y = x-89 since 89 less sociology textbooks were sold compared to bio
Apply substitution to get the following
x+y = 427
x+x-89 = 427 ... replace y with x-89
2x-89 = 427
2x = 427+89
2x = 516
x = 516/2
x = 258 bio textbooks were sold
y = x-89
y = 258-89
y = 169 sociology textbooks were sold
