Question

How many 4-digit multiples of 7 are there?

Answer 1

All the multiples of 7 would be 7, 14, 21, .... k
where k is the largest 4 digit multiple of 7
This is a AP with a= 7 and d = 7

term(n) = a + (n-1)d
7 + (n-1)(7) < 10000 <---- the smallest 5 digit number
7n < 10000
n < 1428.57.. so there are 1428 multiples of 7 with 4 digits or less

7 + (n-1)7 < 1000 <--- the smallest 4 digit number
7n < 1000
n < 142.8

check: term(142) = 7 + 141*7 = 994
so there are 142 multiples of 7 with 3 digits or less

so 1428 - 142 or 1286 of them are multiples of 7

Answer 2

Sir tell smallest four digits number even multiple of 7

Answer 3

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