66. The ratio of the number of boys and girls at a party was 1:2 but when 2 boys and 2 girls left, the ratio became 1:3. then the number of persons initially in the party was
(A) 24
(B) 36
(C) 12
(D) 15
Answer:
Explanation:
67. The HCF of three numbers is 12. If they are in the ratio of 1:2:3, the numbers are
(A) 12, 24, 36
(B) 10, 20, 30
(C) 5, 10, 15
(D) 4, 8, 12
Answer:
Explanation:
68. In 40 litres mixture of milk and water, the ratio of milk and water is 3:1. How much water should be added in the mixture so that the ratio of milk to water becomes 2:1?
(A) 10
(B) 8
(C) 12
(D) 5
Answer:
Explanation:
69. After travelling 60 km, Vivek found that 60 % of his journey was still left. The length of the whole journey is:
(A) 135
(B) 150
(C) 180
(D) 227
Answer:
Explanation:
70. When the determinant of a matrix is zero, the matrix is called
(A) Singular
(B) Non singular
(C) Null
(D) Identity
Answer:
Explanation: