Question

A storybook begins from page 1 to page 233. How many times does the digit ‘2’ appear on all the page numbers?

Answer 1

Hey !!

Here is your answer....

➡ Given :- Storybook has 233 pages total.

➡ To Find :- How many times 2 appears on all page numbers.

➡ Solution :- ' 2 ' appears between 1 - 100 no. pages.

↪ ( 2, 12, 22, 32, 42, 52, 62, 72, 82, 92 ) = 10
↪( 20, 21, 22, 23,..... 29 ) = 10
↪ Total = 20 --------( 1 )

' 2 ' appears between 101 - 200 no. of pages.

↪ ( 102, 112, 122, 132, 142, 152, 162,.... 192 ) = 10
↪ ( 120, 121, 122, 123, 124, .....129 ) = 10
↪( 200 ) = 1
↪ Total = 21 ---------( 2 )

' 2 ' appears between 201 - 233 no. of pages.
↪ ( 201......233 ) = 33
↪ ( 202, 212, 232 ) = 3
↪( 221, 222, 223, 224, ....... 229 ) = 9
↪ ( 220 ) = 1
↪ Total = 46 ----------( 3 )


Now add eq. ( 1 ) , ( 2 ) and ( 3 )

= 20 + 21 + 46
= 87


so, 87 times digit ' 2 ' is appears on page no.
1 to 233.

HOPE IT HELPS YOU..

THANKS ^-^

Answer 2

heya mate

here is your answer

☆ 1st lets count from 1 to 100

(2,12,22,32,42,52,62,72,82,92)

hey dude don't forget to count..... like me

( 20,21,23,24,25,26,27,28,29)

well total numbers we have found are nearly not exactly 11+9 = 20

and count from 100 to 200

(102, 112,122,132,142,152,162,172,182,192 )

here 12 are there

becoz in 122 there are 2digts

ooo still we have

( 120,121,123,124,125,126,127,128,129) = 9

total = 12+9 = 21

now from 200 to 223

( 201,202,203,204.......209) = 10
(210,211,212,213,214......219) = 10
(220,221,222,,,,,229)= 21
(230,231,232,233) = 5

so total = 46

now add all the totals

20+21+46= 87

i hope it helped u

thanks !!!