Question

12 robinete pot umple un bazin in 45 min.Cite robinete pot umole acelasi bazin in 90 min?

Answer 1

1,5 h=90 min
12 robinete=45 min
x robinete=90 min
(12*90):45=24.
Raspuns: Pentru a umple acelasi bazin in 1,5 h este nevoie de 24 de robinete.

Answer 2

12 robinete...........45 minute
? robinete.............90 minute
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$\frac{12*90}{45} = \frac{1080}{45} =24 robinete$