Factor products, divisibility decisions, common multiples and spreadsheet rules.
Example 1
A spreadsheet has 8 in A1. Cell A2 uses =A1+8; this rule is filled down, adding 8 each row. What value is in A12?
Show worked answer
Answer: 96
- The rows hold 8,16,24, …, the multiples of 8.
- Row 12 contains 12×8=96.
Example 2
A program lists positive multiples of 12 and of 9. What is the first number appearing in both lists?
Show worked answer
Answer: 36
- Compare positive multiples of 12 with positive multiples of 9.
- The least common multiple is 36; it is the first shared value.
Example 3
A spreadsheet has 12 in A1. Cell A2 uses =A1+12; this rule is filled down, adding 12 each row. What value is in A10?
Show worked answer
Answer: 120
- The rows hold 12,24,36, …, the multiples of 12.
- Row 10 contains 10×12=120.