0
We will have to count the same number multiple times (i.e., if a number has two fours, it will have to be counted twice). That is what makes this problem sort of tricky. Because the range is pretty small, we can solve it by just thinking it through in small cases:
Case 1: For the numbers: 400-499
- There are 100 digits that start with 4
- There are 10 digits that have a second digit of 4 (i.e., 440-449)
- There are 10 digits have that a last digit of 4 (404, 414, ... , 494)
(note: any type you are counting 0 to 9, you can assume 10 numbers, because the 0 counts as well)
The total number of four's in the interval [400,499] = 100+10+10 = 120
Case 2: For the numbers: 500-599
- There are 0 digits that start with 4
- There are 10 digits that have a second digit of 4 (540 - 549)
- There are 10 digits that have a last digit of 4 (504, 514, ... , 594)
The total number of four's in the interval [500,599] 10+10=20
There is not a third case. The only digit left is 600, and it obviously has no fours.
Therefore your answer is the sum of the two cases: 120 + 20 = 140
The numbers happen to be as follows (note: I've listed each number the number of times four appears, so for example 444 appears 3 times)
400, 401, 402, 403, 404, 404, 405, 406, 407, 408, 409, 410, 411, 412, 413, 414, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424, 424, 425, 426, 427, 428, 429, 430, 431, 432, 433, 434, 434, 435, 436, 437, 438, 439, 440, 440, 441, 441, 442, 442, 443, 443, 444, 444, 444, 445, 445, 446, 446, 447, 447, 448, 448, 449, 449, 450, 451, 452, 453, 454, 454, 455, 456, 457, 458, 459, 460, 461, 462, 463, 464, 464, 465, 466, 467, 468, 469, 470, 471, 472, 473, 474, 474, 475, 476, 477, 478, 479, 480, 481, 482, 483, 484, 484, 485, 486, 487, 488, 489, 490, 491, 492, 493, 494, 494, 495, 496, 497, 498, 499, 504, 514, 524, 534, 540, 541, 542, 543, 544, 544, 545, 546, 547, 548, 549, 554, 564, 574, 584, 594
You can also numerically count your answers with computer code. Here is a script that will give you the answer (it's written in PHP, but it should translate to other languages).
$count = 0;
for ($i=400; $i<601; $i++) foreach (str_split($i) as $digit) if ($digit==4) $count++;
echo $count;
Again the answer is 140.
What else can I help you with?
Wrote numbers 300 to 400 how many times did he write the digal number 3?
120
If you write 300 to 400 how many times do you write 3?
119
How do you write 6.6 million 400 thousand in numbers?
6.6 million 400 thousand in numbers is 7,000,000
How do you write 400 million in numbers?
400,000,000
How do you write 400 billion in numbers?
To write 400 billion in numbers, you would write it as 400,000,000,000. This is because each comma represents a grouping of three digits in the numerical system. So, 400 billion is written as 400 followed by nine zeros.
How many 5 are in between 200 to 400 numbers?
If you write all of the counting numbers from 200 to 400,you will write the digit ' 5 ' forty times.
If you write down all the numbers from 300 to 400 how many times will you write the digit 3?
120 times.
Wrote numbers 300 to 400 how many times did he write the digal number 3?
120
If you write 300 to 400 how many times do you write 3?
119
How do you write 6.6 million 400 thousand in numbers?
6.6 million 400 thousand in numbers is 7,000,000
How many times does the number 2 appear in the numbers 1-400?
180
How do you write 400 million in numbers?
400,000,000
When you write from 1 to 400 how many times do you write 1?
When writing the numbers from 1 to 400, the digit '1' appears in several places. It appears 1 time in the numbers 1 to 9, 10 times in the tens place (10-19), 100 times in the hundreds place (100-199), and 40 times in the ones place across the hundreds (1, 11, 21, ..., 391). In total, '1' is written 1 + 10 + 100 + 40 = 151 times.
How do you write 400 billion in numbers?
To write 400 billion in numbers, you would write it as 400,000,000,000. This is because each comma represents a grouping of three digits in the numerical system. So, 400 billion is written as 400 followed by nine zeros.
How do you write 400 thousand in numbers?
To write 400 thousand in numbers, you would write 400,000. This is a standard way to represent large numbers using commas to separate the thousands, millions, billions, etc. In this case, 400 is followed by three zeros to indicate the thousands place.
How can you write 0.25 percent times 400?
400 *0.25 ------------- 100
What is 75 percent of 400 write and evaluate an expression?
To find 75 percent of 400, you can write the expression as ( 0.75 \times 400 ). Evaluating this expression, ( 0.75 \times 400 = 300 ). Therefore, 75 percent of 400 is 300.
