how many three-digit numbers are divisible by 7?
Answers
Answered by
1
Answer: 128
Step-by-step explanation:
the first three digit number divisible by 7 = 105
the last three digit number divisible by 7 = 994
∴ A.P = 105 , 112 , 119 , ........... , 994.
a = 105
d = 7
aₙ = 994
n = ?
aₙ = a+(n-1)d
994 = 105+(n-1)7
994-105 = 7n - 7
889+7 = 7n
7n = 896
n = 896/7
n = 128
Answered by
1
Answer:
128
Step-by-step explanation:
it forms an AP
105 ,...........,994
a=105
an=994,d=7
so from an =a+(n-1)d
that implies
994=105+ (n-1)7
889=(n-1)7
n-1=889/7=127
n=128
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