Siblings

48 children participated in the school trip. Six of them had one sibling on the trip, nine children had two siblings, and four had three siblings. The others had no siblings on the trip. After returning, their parents were waiting to take the children home by car. Each family arrived in one car. How many cars were waiting for the children?

Final Answer:

n =  36

Step-by-step explanation:

$$\begin{gathered} a=6/2=3 \\ b=9/3=3 \\ c=1 \\ d=48-(2\cdot a+3\cdot b+4\cdot c)=48-(2\cdot 3+3\cdot 3+4\cdot 1)=29 \\ s=2\cdot a+3\cdot b+4\cdot c+1\cdot d=2\cdot 3+3\cdot 3+4\cdot 1+1\cdot 29=48 \\ n=a+b+c+d=3+3+1+29=36 \end{gathered}$$

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