There are 21 numbers from 0 to 100 that are divisible by 5.
Understanding Divisibility by 5
A number is divisible by 5 if it ends in either 0 or 5. We can easily count these numbers within the range of 0 to 100.
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Method 1: Direct Counting: We can list them: 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100. Counting these gives us 21 numbers.
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Method 2: Using Arithmetic Progression: This is a more efficient method. The numbers divisible by 5 form an arithmetic progression with the first term (a) = 0, the common difference (d) = 5, and the last term (l) = 100. The formula to find the number of terms (n) in an arithmetic progression is:
n = (l - a)/d + 1
Substituting the values, we get:
n = (100 - 0)/5 + 1 = 20 + 1 = 21
Therefore, there are 21 numbers between 0 and 100 (inclusive) that are divisible by 5. This confirms the count obtained by direct listing. The provided reference mentioning 19 numbers likely excluded 0 or 100 from the count.
References: The provided references support the methodology of identifying multiples of 5 and calculating their quantity. The discrepancies in some references regarding the exact number are likely due to differences in whether the endpoints (0 and 100) were included in the counting.