Pizza

Five friends were together for pizza. Adam divided his pizza into thirds, Boris in quarters, Denis in patina, and Luke in sixth. Then Simon also came to them. Every five boys gave him one piece, leaving him one whole pizza. How many equal parts did Ivan slice his pizza in?

Correct answer:

i =  20

Step-by-step explanation:

$$\begin{gathered} 1/3+1/4+1/5+1/6+1/i=1 \\ i/3+i/4+i/5+i/6+1=i \\ 3i=60 \\ i=\frac{60}{3}=20 \\ i=20 \end{gathered}$$

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