IPMAT/Modern Math•12mos
solulu

Permutation combination

In how many ways can 7 identical erasers be distributed to 4 children in such a way that each kid gets at least 1 eraser but nobody gets more than 3 erasers?

I'm getting the answer as 20 but the ans is 16

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Comments (2)

S
solulu
OP•12mos

Okay thank you

1
B
basicallybhavesh
IIM Ranchi (IR 2)
MOD•12mos
Correct

Counting arrangements:

Type 1: (1, 1, 2, 3) This means two children get 1 eraser, one gets 2 erasers, and one gets 3 erasers.

Number of arrangements = 4!/(2!) = 24/2 = 12 ways

Type 2: (1, 2, 2, 2)

This means one child gets 1 eraser and three children get 2 erasers each.

Number of arrangements = 4!/(3!) = 24/6 = 4 ways

Total: 12 + 4 = 16 ways

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