Question
The diameters of three inlet pipes of a cistern are 1.5
cm, 2 cm and 2.5 cm respectively. The pipe with the maximum diameter can alone fill up the cistern in 3 hours and 36 minutes. Find the time in which the empty cistern will be filled if all the three inlet pipes are opened together.Solution
Diameters of three inlet pipes of a cistern = 1.5 : 2 : 2.5 = 3:4:5 Ratio of efficiency will be = Square of diameter => 9 : 16 : 25 Total work = Time x Maximum diameter efficiency = 216 min x 25 If all three work = (216 x 25)/50(9+16+25) = 108 min = 1 hour 48 min
15.99% of 549.99 ÷ 11.17 = ? ÷ 20.15
74.91% of 639.95 – 599.98% of 45 + 119.987 = ?
(4.88 × 5.76)2 - ?2 = 39.89 × 19.86
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exactvalue.)
(1800.23 ÷ 29.98) + (816.32 ÷ 23.9) + 1634.11 = ?
1449.98 ÷ 50.48 × 10.12 = ? × 2.16
36.05 × 5.02 + 12.052 = ? + 9.09 × 4.04Â
(31.9)3 + (34.021)² - (16.11)3 - (42.98)² = ?