NCERT Figure it Out 1 - Q5 (pebbles) - Number Play

Question: Pebble riddle: remainder 1 when grouped by 3; odd; remainder 1 when grouped by 5; divisible by 7; less than 100. How many pebbles?

Answer: 91 pebbles.

Full step-by-step NCERT solution with diagrams on Something by Zero.