Question
The average age of a group of 80 students is 14 years.
If 3 students whose ages are 16 years, 22 years, and _____ years are replaced by 3 new students whose ages are _____ years, 20 years, and 32 years, then the new average age of the group increases by 0.25 years. The values given in which of the following options will fill the blanks in the same order to make the above statement true: I. 28, 39 II. 35, 46 III. 23, 34Solution
ATQ, Since the new average increases by 0.25 years, the difference in the sum of ages of the students who left and the new students should be: 80×0.25=20 years Option I: (39+20+32)−(16+22+28)=25 years So, option I cannot be the answer. Option II: (46+20+32)−(16+22+35)=25 years So, option II cannot be the answer. Option III: (34+20+32)−(16+22+23)=25 years So, option III cannot be the answer.
11   33   66   112   173    ?  . Â
324 322 640 1914 7648 ? 229368
...Find sum of first n terms: 2 + 6 + 12 + 20 + 30 + …
351Â Â Â 261Â Â Â 181Â Â Â 111Â Â Â 51Â Â Â ?
If Series II follows the same pattern as Series I, then determine the value of 'p'.
Series I: 36, 38, 48, 78, 146, 276
Series II: 49, __, __, __, __, p.
17                          26                          37                   �...
32, 8, 4, ?, 3, 3.75
40    42    87    266    ?     5366
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...
7Â Â Â Â Â Â 15Â Â Â Â Â Â Â 31Â Â Â Â Â Â 63Â Â Â Â Â Â 127Â Â Â Â Â Â ?
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