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A number of teachers were to receive 6 pens each but needed 4 more pens for them to be equally divided.
If each teacher received 9 pens, 25 more pens would be necessary.how many pens are there?
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Let p = # of pencils, and n = # of teachers.
The first part of the condition says that p + 4 = 6n. (1)
The second part says that p + 25 = 9n. (2)
Distract the first equation from the second one. You will get
25 - 4 = 3n, or n = = 7.
Then from (1) you will get p = 6n - 4 = 6*7 - 4 = 42 - 4 = 38.
Answer. 7 teachers and 38 pens.