Question
A printer uses a total number of 4893 digits in order to
number all the pages of his book. He starts with the digit 1 for the first page of the book. How many pages does the book have?Solution
1.digit pages = 1 to 9 = 9 2.digits pages = 10 to 99 = 90 3.digits pages = 100 to 999 = 900 4 digit pages = let’s say x Now, Number of digits used till 999 pages = 9*1 + 90*2 + 900*3 = 9 + 180 + 2700 = 2889 Therefore, 4x + 2889 = 4893 4x = 2004 X = 501 So, total pages are 9 + 90 + 900 + 501 =1500
What value should come in the place of (?) in the following questions?
√? + 10 * 18 + 16 * 4 = 280
104 × 21 ÷ 13 + ? % of 300 = 320 + 22
√4096 + 4/5 of 780 − ? = 296
236.23 - 653.23 + 696.23 = ?
60 = (? x 10 + 250)/5
(5832) 2/3 / (104976)3/4 X ? = ( `sqrt(18)` ` ` ) 5
...What will come in the place of question mark (?) in the given expression?
(30 × 5 + 20) × 2 = ?
25.6% of 250 + √? = 119
What value should come in place of the question mark (?) in the following question?
(286 ÷ 11 + 14) × 5 = 40 + 25% of ?<...
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