Multiplication rule will be used to find the number of cadets in the given number of rows.
In a row, number of cadets `=5`
When number of rows are `n`.
Total number of cadets `=` Number of cadets in a row `×` Number of rows
`= 5 × n `
`= 5n`
Hence, the rule which gives the number of cadets in given number of rows is `5n`.