Question

4. Find the number of 7's between 100 and
700.
(a) 120
(b) 101
(C) 121
(d) 100​

Answer 1

Answer:

85 is the correct answer

Step-by-step explanation:

check your options correct

because 1to 700

100 number are present of 7's

Answer 2

The number of sevens between 100 and 700 is 120.

Solution:

We need to determine number of sevens between 100 and 700.

Let’s first see how many sevens are there between 100 to 200.

From 100 to 200 there are 10 sevens at ones place that are 107, 117, 127, …… 197

And 10 sevens on tens place that are 170, 171, 172 , …… 179.

So in total there are 20 sevens in 100 to 200.

Similarly for each hundred that is 300 to 400, 400 to 500 , 500 to 600 and 600 to 700 ( excluding 700) there are 20 sevens

So number of sevens = 20 x number of hundreds  

=> Number of sevens = 20 x 6 = 120

Note that we have not considered seven of 700 as number of sevens are asked between 100 and 700.  

So number of sevens between 100 and 700 (excluding extremes that is 100 and 700) is 120.