Given 30M+15R=900, if M=15, how many jobs did Rodney have for raking leaves?

Given 30M+15R=900, if M=15, how many jobs did Rodney have for raking leaves?

• A. 15
• B. 20
• C. 30
• D. 90

Answer: (C)

To solve the equation 30M + 15R = 900 and find out how many jobs Rodney had for raking leaves when M (the number of jobs Mary had) is equal to 15, substitute 15 for M in the equation. First, calculate 30 times M (30 * 15): 30 * 15 = 450. Now, substitute this value back into the original equation: 450 + 15R = 900. Next, isolate the term that contains R by subtracting 450 from both sides: 15R = 900 - 450, 15R = 450. Finally, divide both sides by 15 to solve for R: R = 450 / 15, R = 30. This shows that Rodney had 30 jobs for raking leaves. The process of substituting M into the equation and performing basic arithmetic operations confirms the answer.

To solve the equation 30M + 15R = 900 and find out how many jobs Rodney had for raking leaves when M (the number of jobs Mary had) is equal to 15, substitute 15 for M in the equation.

First, calculate 30 times M (30 * 15):

30 * 15 = 450.

Now, substitute this value back into the original equation:

450 + 15R = 900.

Next, isolate the term that contains R by subtracting 450 from both sides:

15R = 900 - 450,

15R = 450.

Finally, divide both sides by 15 to solve for R:

R = 450 / 15,

R = 30.

This shows that Rodney had 30 jobs for raking leaves. The process of substituting M into the equation and performing basic arithmetic operations confirms the answer.