Question
If p = 20 - q - r and pq + r(p + q) = 154, then find the
value of (p² + q² + r²).Solution
We have, p = 20 - q - r
So, p + q + r = 20
And, pq + r(p + q) = 154
Or, pq + qr + pr = 154
Using, (p + q + r)² = p² + q² + r² + 2(pq + qr + pr)
20² = (p² + q² + r²) + 2 × 154
400 = (p² + q² + r²) + 308
p² + q² + r² = 92
The current average age of Raghav and Pooja is 34 years. After 6 years, the ratio of their ages will be 7:9. Find Pooja’s age 5 years ago.
The ratio of the present ages of P and Q is 8:7 respectively. If the age of P 10 years hence from now will be 100% more than the age of Q 4 years ago fr...
A girl’s age is 160% of what it was 5 years ago, but 80% of what it will be after 6 years. What is her present age?
- Twelve years ago, Pawan's age was twice that of Qureshi. Thirteen years from now, the ratio of their ages will be 9:7. What is their current average age?
Three years ago, the ratio of ages of P, Q, and R was 4:3:5. Present age of S is 40 years, who is 5 years older than R. Find the age of P five years fro...
The average age of A, B and C is 30 years, while the average age of B, A and D is 20 years. If the ratio of the age of C and D is 5:3, respectively, the...
Present age of Vikrant is 40% less than the present age of Priya. Age of Vikrant 4 years ago was 50% the present age of Priya. Find the present averag...
A’s present age is double B’s present age. After 6 years, A’s age will be four times the present age of C. The ratio of B’s age 3 years ago to C...
The present age of A is 5/3 times to that of his marriage age. Present age of his brother is 1/3rd of his present age. If A was married 24 years ago the...
The respective ratio of the present ages of A and B is 7:6. The present age of C is 10% more than that of B. The sum of the present ages of A, B and C i...
Relevant for Exams:
