How many numbers are there between 1 to 200 which are divisible by 3 ...
The first number divisible between 1 and 200 is 3 and the last one is 198
We know that tn = a + (n - 1)d
198 = 3 + (n - 1)3
n = 66
so there are 66 terms divisible by 3 between 1 and 200
the terms which is divisible by 3 and 7 both are multiple of 21
so last term divisible by 21 between 1 and 200 is 189
189 = 21 + (n - 1)21
n = 9
Number of terms which are divisible by 3 but not by 7 = 66 - 9
= 57
Hence, the correct option is (c).
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How many numbers are there between 1 to 200 which are divisible by 3 ...
To find the numbers between 1 to 200 that are divisible by 3 but not by 7, we can use the concepts of divisibility and counting.
Step 1: Find the numbers divisible by 3
To find the numbers divisible by 3, we need to check if each number between 1 and 200 is divisible by 3. We can do this by dividing each number by 3 and checking if the remainder is 0.
Step 2: Find the numbers divisible by 7
Similarly, we need to check if each number between 1 and 200 is divisible by 7. If the remainder is 0 when dividing a number by 7, it is divisible by 7.
Step 3: Find the numbers divisible by 3 but not by 7
To find the numbers that are divisible by 3 but not by 7, we need to find the numbers that are divisible by 3 but have a remainder when divided by 7.
Step 4: Count the numbers
Finally, we count the numbers that meet the criteria of being divisible by 3 but not by 7.
Now, let's break down the steps and solve the problem.
Step 1: Find the numbers divisible by 3
To find the numbers divisible by 3, we divide each number between 1 and 200 by 3 and check if the remainder is 0.
Step 2: Find the numbers divisible by 7
To find the numbers divisible by 7, we divide each number between 1 and 200 by 7 and check if the remainder is 0.
Step 3: Find the numbers divisible by 3 but not by 7
To find the numbers that are divisible by 3 but not by 7, we look for numbers that have a remainder when divided by 7.
Step 4: Count the numbers
Finally, we count the numbers that meet the criteria of being divisible by 3 but not by 7.
The correct answer is option 'C' which states that there are 57 numbers between 1 and 200 that are divisible by 3 but not by 7.
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