Answer :
To solve this problem, we need to find out how many office buildings can be washed with the available supplies when a school with 42 windows is also being cleaned. Altogether, there are enough supplies to clean a total of 126 windows.
Let's break it down step by step:
1. Define Variables:
- Let [tex]\( x \)[/tex] represent the number of office buildings.
- Each office building has 21 windows.
2. Set Up the Equation:
- The cleaner can wash the windows of the office buildings and the school.
- The total number of windows that can be washed (from both the office buildings and the school) is 126.
- So, the equation accounting for both the office buildings and the school is:
[tex]\[
21x + 42 = 126
\][/tex]
3. Solve the Equation:
- First, subtract 42 (the number of windows in the school) from both sides to focus on the office buildings:
[tex]\[
21x = 126 - 42
\][/tex]
[tex]\[
21x = 84
\][/tex]
- Next, divide both sides by 21 to solve for [tex]\( x \)[/tex]:
[tex]\[
x = \frac{84}{21}
\][/tex]
[tex]\[
x = 4
\][/tex]
Therefore, 4 office buildings can be washed with the available supplies. The correct equation to use for solving this problem is:
[tex]\[
21x + 42 = 126
\][/tex]
Let's break it down step by step:
1. Define Variables:
- Let [tex]\( x \)[/tex] represent the number of office buildings.
- Each office building has 21 windows.
2. Set Up the Equation:
- The cleaner can wash the windows of the office buildings and the school.
- The total number of windows that can be washed (from both the office buildings and the school) is 126.
- So, the equation accounting for both the office buildings and the school is:
[tex]\[
21x + 42 = 126
\][/tex]
3. Solve the Equation:
- First, subtract 42 (the number of windows in the school) from both sides to focus on the office buildings:
[tex]\[
21x = 126 - 42
\][/tex]
[tex]\[
21x = 84
\][/tex]
- Next, divide both sides by 21 to solve for [tex]\( x \)[/tex]:
[tex]\[
x = \frac{84}{21}
\][/tex]
[tex]\[
x = 4
\][/tex]
Therefore, 4 office buildings can be washed with the available supplies. The correct equation to use for solving this problem is:
[tex]\[
21x + 42 = 126
\][/tex]