Question

Question 2: show working out

Answer 1

Answer in fraction form is exactly 2/27 
Answer in decimal form is approximately 0.07407

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Explanation:

4 people play both,9 play flat flute only, 12 play piano only.
So 4+9+12 = 13+12 = 25 people play one instrument only or they play both.

We have 27 people total meaning that 27-25 = 2 play neither instrument.

Divide the values 2 and 27 to get
2/27 = 0.07407
this value is approximate (rounded to five decimal places)