r=125÷2=62,5cm = 6,25dm h=2,45m =24,5dm
v=π×r²×h =3,14 × (6,25)² × 24,5 =3,14 × 39,0625 × 24,5 =3005,08dm³
=3005,08litres
3005,08 x 3/4 =2253,81 litres
3litres...................1h
2253,81 litres................x
x= 2253,81 × 1/3 ≈ 751h = (24x 31 +7)h =31jours 7heurs