How many multiples of 4 lie between 10 and 250?
60 multiples of 4 lie between 10 and 250.
Explanation
This question requires finding the count of multiples of 4 in a given range. The multiples of 4 form an Arithmetic Progression. We identify the first and last multiples within the range, then use the nth term formula to find the number of terms.
Solution Steps
Step 1: Identify the first multiple of 4 greater than 10. Since 10 ÷ 4 = 2.5, the next integer is 3. So, first term a = = 12.
Step 2: Identify the last multiple of 4 less than 250. Since 250 ÷ 4 = 62.5, the integer part is 62. So, last term l = = 248.
Step 3: The multiples of 4 form an AP: 12, 16, 20, ..., 248 with first term a = 12, common difference d = 4, and last term l = 248.
Step 4: Apply the formula l = a + (n - 1)d
248 = 12 + (n - 1) × 4
236 = (n - 1) × 4
n - 1 = 59
n = 60