Question
Four lights blink at intervals of 18 seconds, 24
seconds, 36 seconds, and 48 seconds respectively. How many times will all the lights blink together in 3 hours?Solution
ATQ,
All the lights will blink together after 144 seconds (LCM of 18, 24, 36 and 48)
3 hours = 180 minutes
Therefore, required number of times ≤ (180 × 60) ÷ 144 = 75
41 28 ? 15 67 2
3 15 35 63 99 ?
4                14                  130                     512                �...
1 1 8 4 27 9 81
...Select the number from among the given options that can replace the question mark (?) in the following series.
24, 35, 51, 73, 102, ?
4 5 12 39 160 ?
...10, 22, 46, ?, 130, 190
3  16  22  ?   98   206
542Â Â Â Â Â Â 541Â Â Â Â Â Â Â 532Â Â Â Â Â Â Â 507 Â Â Â Â Â Â Â 458Â Â Â Â Â Â Â ?
...If   314     306      x      269       394    178    1480
Then, 1/3 x + 2x - x = ?
...
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