Question
A boy goes to school with a speed of 55 km/h and comes
back with a speed of 45 km/h. find his average speed?Solution
Since the distance travelled by a boy (going to school and coming back from school) is equal. So, average speed = 2xy/(x + y) Average speed = (2 x 55 x 45)/(55 + 45) Average speed = (2 x 55 x 45)/100 = 49 km/hr
13, 14, 18, 27, 43, ?
642 202 541 312 523 ?
...6 10 ? 210 1672 16710
...3 5 7 25 85 481
...19   20   42   129   ?    2605  . Â
2 3 3 ? 49 254
...147      138       120      93      ?      12
...The question below is based on the given series I. The series I satisfy a certain pattern, follow the same pattern in series II and answer the questions...
31   48    67    90   ?      150
14 8 6 4 7 8.5
...