Question
A tank can be filled by a tap in 10 minutes and by
another tap in 30 minutes. Both the taps are kept open for 5 minutes and then the first tap is shut off. After this, the tank, will be completely filled in what time?Solution
Part filled by Tap A in 1 minute = 1/10 Part filled by Tap B in 1 minute = 1/30 (A+B)’s 5 minute work = 5 × (1/10+1/30) = 5 × ((3+1)/30) = 5 × (4/30) = 2/3 Remaining work = 1 - 2/3 = 1/3 1/30 Part filled by Tap B in = 1 minute 1/3 Part will be filled in = (1/3)/(1/30) = 30/3 = 10 minute Alternate method: Let total capacity of tank = LCM(10, 30) = 30 L So A can fill in 1 minute = 30/10 = 3L & B can fill in 1 minute = 30/30 = 1L So Both taps together filled in 5 minutes =( 3+1)×5 = 4×5 = 20 L So remaining tank = 30 – 20 = 10 So this 10L is completed filled by B tap = 10/1 =10 minutes
What will come in the place of question mark (?) in the given expression?
75% of (β64 Γ 8 - 16) Γ ? = 15Β²
(8.6 Γ 8.6 + 4.8 Γ 4.8 + 17.2 Γ 4.8) Γ· (8.62 β 4.82 ) = ? Γ· 19
6 0 - 20 [8 + 12 {8-8 (20-12)+20}-40] ÷ 16 =?
- What will come in place of the question mark (?) in the following questions?
144Γ·12+18Γ2=? 75% of 65% of 7/5 of 2420 = ?
Find the simplified value of the given expression:
1.82Β + 2.42Β + 1.52Β - 1.8 x 2.4 - 2.4 x 1.5 - 1.8 x 1.5
(β 196 x β 36 x β 100) = ?% of 200
72% of 486 β 64% of 261 = ?
35% of 240 β 6 2 = ? 2 β β256