Question
If p = 50 - q - r and pq + r(q + p) = 816 then find the
value of (p2Â + q2Â + r2) .Solution
We have, p = 50 - q - r
So, p + q + r = 50
And, pq + r(q + p) = 816
Or, pq + qr + pr = 816
Using, (p + q + r)Â 2Â = p2Â + q2Â + r2Â + 2(pq + qr + pr)
So, 502Â = (p2Â + q2Â + r2) + 2 X 816
Or, p2Â + q2Â + r2Â = 2,500 - 1,632
So, p2Â + q2Â + r2Â = 868
Cost of two types of pulses is Rs.15 and Rs, 25 per kg, respectively. If both the pulses are mixed together in the ratio 2:3, then what should be the pr...
A shopkeeper mixes two varieties of sugar costing Rs. 36 per kg and Rs. 48 per kg in such a way that the mixture costs Rs. 42 per kg. In what ratio are ...
A person purchased petrol and kerosene oil for Rs.62 per litre and Rs 55 per litre respectively. In what ratio should petrol be mixed with kerosene oil ...
Out of 10 men, 3 are wearing red caps, 4 are wearing green caps, and the remaining men are wearing orange caps. They are to be seated in a linear row. I...
58     69      56       ?      54       73
...‘A’ and ‘B’ can do a piece of work in 25 days and 30 days, respectively. If they started the work together and worked on it for 5 days, then fin...
A shopkeeper mixes two varieties of rice costing Rs 48 per kg and Rs 60 per kg to get a mixture worth Rs 55 per kg. In what ratio (by weight) should he ...
4, 14, 44, 134, ?, 1214
In what ratio coffee at 285 Rs/kg should be mixed with the coffee at 320 Rs/kg so that after mixture its rate become 300 Rs/kg if the quantity of 1st ty...
A vessel is full of a mixture of kerosene and petrol in which there is 18% kerosene, 8 litre are drawn off and then the vessel is filled with petrol. Re...
Relevant for Exams:
