Question:

Look at the sequence of numbers on one column of the Ishango bone: 11, 13, 17, 19. What do these numbers have in common? List the next three numbers that fit this pattern. [Page No. 43]

Answer: Verified

All the numbers 11, 13, 17, 19 are prime numbers.
They have no divisors other than 1 and themselves.
The next three primes after 19 are: 23, 29, 31.
Caution
Students should understand the clear difference between prime and composite numbers. Prime numbers have no factors other than 1 and the number itself, whereas composite numbers have at least one factor other than 1 and the number itself.
Note that 1 is neither prime nor composite.

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Look at the sequence of numbers on one column of the Ishango bone: 11, 13, 17, 19. What do these numbers have in common? List the next three numbers that fit this pattern. [Page No. 43]

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