“I hold some pebbles, not too many, When I group them in 3’s, one stays with me. Class 8
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“I hold some pebbles, not too many, When I group them in 3’s, one stays with me. Class 8
Question 1.
“I hold some pebbles, not too many, When I group them in 3’s, one stays with me.
Try pairing them up — it simply won’t do,
A stubborn odd pebble remains in my view.
Group them by 5, yet one’s still around, But grouping by seven, perfection is found.
More than one hundred would be far too bold,
Can you tell me the number of pebbles I hold?” Class 8
Solution:
Number of pebbles = (LCM of 3 and 5) + 1 = 15 + 1 = 16. It is not divisible by 7. So, not possible.
It may be (a multiple of 15) + 1 i.e., 15x + 1.
But 15x + 1 must be divisible by 7 also.
So, the number of pebbles = 15 × 6 + 1 = 91.
It is also less than 100.