Quantitative Aptitude - Arithmetic Ability Questions

The average weight of 25 candles is 40 grams. If some candles of weight 50 grams each were removed, then average weight becomes 37.5 grams. How many candles of weight 50 grams each were removed? 

The average of 10 numbers is X and one of the number is 38. If 38 is replaced with 19, then what will be the new average?

The mean of 12 observations is 15. One more observation is included and the new mean becomes 16. The 13th observation is

After 10 innings the average score per innings of a batsman was 52. After 12 innings the average rose to 54. If the batsman had scored 16 more runs in the 12th innings than in the previous one, how many runs did he score in the 11th innings?

In a cricket match, the scores of the players are considered such that coefficient of variation of scores is 16 and mean is 25 then the variance is

What will be the average of the first 7 positive odd numbers divisible by 5?

The median of the data -3, 4, 0, 4, -2, -5, 1, 7, 10, 5 is

The median of the data 1, 1/2, 1/2, 3/4, 1/4, 2, 1/2, 1/4, 3/4 is