Question

Which of the following is the best starting point for approximating the square root of to the nearest whole number?

√1<√73<100
√64<√73<√81
√72<√73<√74
√70<√73<√80

Answer 1

i suppose its the second option because the two outside values are 8 and 9 (i think!)
73 is close to 81 than to 64 so square root is 9 to neares whole number

Answer 2

one useful way of sqaure two numbers ending in 0.5 is
for example
8.5 * 8.5 = 8*9 + 0.25 = 72.25