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How Many Three-digit Number are Divisible by 7?
By BYJU'S Exam Prep
Updated on: September 25th, 2023
Do you know how many 3-digit numbers are divisible by 7? The answer is 128. But how did we find that out? To find out how many three-digit number are divisible by 7, we must go through the following steps.
Step 1 – Identify that the given sequence is an AP or arithmetic progression
Step 2 – Find out the number of terms in the given AP
Scroll down to find out how to calculate and find out how many three-digit numbers are divisible by 7.
Table of content
Answer:
128 three-digit numbers are divisible by 7
Now, let’s find out how we can reach this answer by following the abovementioned steps.
So, the first 3-digit number divisible by 7 is 105, and the last 3-digit divisible by 7 is 994.
Hence, the sequence of numbers will be something like 105, 112,_____, 994. As you can see, this is an arithmetic progression with a difference of 7 between the numbers.
Now, to find the number of terms in the AP:
The nth term of an AP is given by: an=a+(n−1)d
Here, A is the first term, and n is the term
Also, d is the common difference between the terms
So, an−>nth term
Hence, a= 105, an= 994 and d= 7
994 = 105 + (n-1)7
889 = 7n – 7
7n = 896
n = 128
Hence, we can say that 7 is divisible by 128 three digit numbers
Summary:
How Many Three-digit Number are Divisible by 7?
The answer to how many three-digit number are divisible by 7 is 128. To calculate this, you must understand that this is an arithmetic progression with a common difference of 7. Read the article above to understand how to reach the answer and find out how many 3-digit numbers are divisible by 7.
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