If (x + y) : (x - y) = 7 : 3 then find the ratio (x3 + y3) : (x3 - y3)
133/117
Let x + y = 7k and x - y = 3k.
Adding: 2x = 10k, so x = 5k. Subtracting: 2y = 4k, so y = 2k.
x3 + y3 = 125k3 + 8k3 = 133k3
x3 - y3 = 125k3 - 8k3 = 117k3
Ratio = 133/117
Check: (5 + 2) : (5 - 2) = 7 : 3, as given, and 133/117 cannot be reduced further because 133 = 7 × 19 and 117 = 9 × 13 share no common factor.
Hence, 133/117.
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In a mixture of 156 litres, the ratio of milk and water is 7 : 6. How much water should be added to make the ratio 14 : 13?
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The third proportional to 9 and 15 is:
The average age of 3 persons is 30 years.If their ages are in the ratio of 3 : 5 : 7 respectively, then the age of the eldest person is:
The income of A and B are in the ratio 5 : 3. The expenses of A, B and C are in the ratio of 8 : 5 : 2. If C spends 2000 and B saves ₹ 700, then A saves:
