61.11, 22, 33, 44, ? (number series)
Ans:55
62.81, 27, 9, 3, ? (number series)
Ans:1
63.3, 9, 27, 81, ? (number series)
Ans:243
64.64, 32, 16, 8, ? (number series)
Ans:4
65.Average of 10, 20, 30 = ?
Ans:20
66.Average of 5, 15, 25, 35 = ?
Ans:20
67.Average of the first 5 natural numbers = ?
Ans:3
68.Average of 12, 18, 24 = ?
Ans:18
69.Average of 40, 50, 60 = ?
Ans:50
70.Average of the first 10 natural numbers = ?
Ans:5.5
71.Average of 2, 4, 6, 8, 10 = ?
Ans:6
72.Simplify the ratio 15 : 25.
Ans:3 : 5
73.Simplify the ratio 12 : 18.
Ans:2 : 3
74.3/4 of 80 = ?
Ans:60
75.2/5 of 100 = ?
Ans:40
76.7/8 of 64 = ?
Ans:56
77.5/6 of 72 = ?
Ans:60
78.Convert 0.25 to a fraction.
Ans:1/4
79.Convert 3/5 to a decimal.
Ans:0.6
80.LCM of 4 and 6 = ?
Ans:12