Let the number be x.
First student increased the number by 23, therefore
⇒ x + 23
Second student decreased the number by 1, therefore
⇒ x - 1
The first student's result was 7 times greater than the result of the second student's, therefore
⇒ x + 23 = 7(x - 1)
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Solve for x:
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x + 23 = 7( x- 1)
x + 23 = 7x - 7
6x = 30
x = 5
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Answer: The number on the board is 5.
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As we look at the question Answer is :12x +15
Answer:
B
Step-by-step explanation:
2a+45=180
subtract 45 from both sides which equals 2a=135
divide both sides by 2 which would solve for a.
Given:
12 students average 70%
18 students average 80%
What is the overall average of the 30 students as a percent?
12 x 70% = 840%
18 x 80% = 1440%
840% + 1440% = 2280%
2280% / 30 = 76%
The overall average of the 30 students is 76%.
