In this task, you need to provide the correct option for a given problem from the provided options.
--------
Question: Problem: the least whole number which when subtracted from both the terms of the ratio 6 : 7 to give a ratio less than 16 : 21 , is ?
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7

Answer: a

Question: Problem: what is the square root of 6,561 ?
Options: a ) 18 , b ) 9 , c ) 45 , d ) 62 , e ) 81

Answer: e

Question: Problem: sandy is younger than molly by 14 years . if the ratio of their ages is 7 : 9 , how old is sandy ?
Options: a ) 42 , b ) 49 , c ) 56 , d ) 63 , e ) 70

Answer:
b