Estimate which is bigger : 100 + 25 or 90 + 15

If we multiply a number by the number itself, we get the square of the number and square root of a number is a value, which on multiplication by itself gives the original number. For example, if m and n are natural numbers such that m can be expressed as n 2 , that is m = n 2 or we can expressed as m = n × n Thus, we get 100 + 25 = 10 + 5 = 15 And, 90 + 15 = 9 . 5 + 3 . 9 = 13 . 4 So, the bigger is 100 + 25

Estimate which is bigger : 100 + 25 or 90 + 15

If we multiply a number by the number itself, we get the square of the number and square root of a number is a value, which on multiplication by itself gives the original number. For example, if m and n are natural numbers such that m can be expressed as n 2 , that is m = n 2 or we can expressed as m = n × n Thus, we get 100 + 25 = 10 + 5 = 15 And, 90 + 15 = 9 . 5 + 3 . 9 = 13 . 4 So, the bigger is 100 + 25

Use the number line to estimate a value for 40 .

Given number: 40 We know, 6 2 = 36 and 7 2 = 49 Now, 36 < 40 < 49 ∴ 36 < 40 < 49 and 36 = 6 , 49 = 7 Therefore, 6 < 40 < 7 Now, 40 is the number between 36 and 49 . ∴ 40 is the number between 6 and 7 . Finding halfway between 36 and 49 : 36 + 49 2 = 85 2 = 42 . 5 40 is closer to 36 than 49 . ⇒ 40 is closer to 6 than 7 . ∴ A sensible estimate of 40 will be 6 . 3 and 6 . 4 .