Question
Download Solution PDFThere are four bells which ring at an interval of 15 minutes, 25 minutes, 35 minutes and 45 minutes respectively. If all of them ring at 9 A.M., how many more times will they ring together in the next 72 hours ?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept:
LCM: LCM is the product of the greatest power of each prime factor, involved in the numbers.
Calculation:
LCM of 15, 25, 35, and 45.
15 = 3 × 5
25 = 5 × 5
35 = 5 × 7
45 = 3 × 3 × 5
LCM = 32 × 52 × 7 = 1575 min = 26.25 hr
It menas, bell ring at every 26.25 hr
Since, 72/26.25 = 2.74
Therefore, In 72 hr, bell rings 2 times.
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