Multiple choice

For the past m days, the average daily production at a factory was 40 gadgets. If today's production of 100 gadgets increases the average to 45 gadgets per day, what is the value of m?

  1. 20

  2. 15

  3. 11

  4. 8

  5. 5
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let the total production for m days be 40m. After adding 100, the new total is 40m + 100, and the new count is m + 1. The equation (40m + 100) / (m + 1) = 45 gives 40m + 100 = 45m + 45, so 5m = 55, which means m = 11.

AI explanation

The total production for the past m days is 40 multiplied by m, and the new total including today is 40m plus 100. The new average is calculated as (40m plus 100) divided by (m plus 1) equals 45. Solving this equation, 40m plus 100 equals 45m plus 45, which simplifies to 5m equals 55, giving m equals 11.

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