Question
A 120 litres solution of alcohol and water contains 30%
alcohol. When Q litres of alcohol and (Q - 4) litres of water are added to the solution, the quantity of alcohol becomes 3/7 of the total solution. What is the value of (Q - 13)?Solution
ATQ,
Quantity of alcohol in the initial solution = 0.30 Γ 120 = 36 litres Quantity of water in the initial solution = 120 - 36 = 84 litres ATQ: 36 + Q = (3/7) Γ (120 + Q + Q - 4) β 36 + Q = (3/7) Γ (120 + 2Q - 4) β 36 + Q = (3/7) Γ (116 + 2Q) β 7(36 + Q) = 3(116 + 2Q) β 252 + 7Q = 348 + 6Q β Q = 96 Required value = Q - 13 = 96 - 13 = 83
[1.45 X 1.45 X 1.45 + 0.55 X 0.55 X 0.55 + 4.785] = ?
(125 × 12 × √8100) ÷ 150 = ?
[β(91125/19683Β )- β(3375/5832Β )Β ] Γ β(512/9261)Β = ? - β(484/3969)
- 60% of 180 β 30% of 60 = 15% of ?

27% of 250 – 0.02% of 1000 is equal to:
- What will come in the place of question mark (?) in the given expression?
32% of 74% of ? = 16% of 37% of 180 What value should come in the place of (?) in the following questions?
?2 = 240 * β25 + 38 * 5 - 94
?2 + 114 - 48 Γ· 2 Γ 5 = 163
18 + 28 ÷ 4 - 14 = ? - 35
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