Question
Length and breadth of a rectangular field is (x + 5) cm
and (x – 4) cm, respectively. If the cost of ploughing the field at a rate of Rs. 7 per cm² is Rs. 3087, then find the cost of fencing the field at a rate of Rs. 18 per cm.Solution
ATQ, Area of the field = 3087/7 = 441 cm² So, (x + 5)(x – 4) = 441 Or, x² + x – 441 = 0 Or, x² + 21x – 20x – 441 = 0 Or, x(x + 21) – 21(x + 21) = 0 Or, (x + 21)(x – 21) = 0 So, x = 21 Perimeter of the field = 2 × {(21 + 5) + (21 – 4)} = 86 metres Desired cost = 86 × 18 = Rs. 1548
84 is divided into two parts in such a way that the fourth part of the first part and the fifth part of the second are in the ratio 1 : 2. The first par...
In a class, the ratio of students who passed to those who failed is 5:6. If 30 additional students had passed the exam, the ratio would shift to 17:16. ...
P, Q and R together started a business. Four times the investment of P equals five times the investment of Q and the capital of Q is twice that of R. Fi...
The ratio of P’s to Q’s salary is 5 : 7. If Q’s salary is increased by 35%, his total salary becomes Rs. 52,920. What is the salary of P?
Rs. 23121 are divided between A and B in the ratio 2:7. What is the difference between thrice the share of A and twice the share of B?
What is the mean proportion between 3 and 27?
Marks scored by A and B in a test are in the ratio 12:5 respectively. If B had scored 5 more marks, then marks scored by A would be 20% more than that o...
Two numbers are in the ratio 7:4. After adding 2 and 6 to them respectively the ratio becomes 2:3. Find the bigger number.
A vessel contains some milk .6 liter of the milk was taken out of the vessel and replaced with 6 liter of water and again 6 liter of mixture was taken o...
The cost of diamond varies directly as the square of its weight. A diamond broke into four pieces with weights in the ratio 2 : 3 : 5 : 6. if the loss i...
Relevant for Exams:
