Question

How many 3 digit positive integers exist that when divided by 7 leave a remainder of 5?
Select one:
a. 142
b. 129
C. 141
d. 128​

Answer 1

Answer:

b. 129

Step-by-step explanation:

First three digit number which when divided by 7 leaves remainder 5 is 103. here's how.

14*7=98

98+5=103.

next number will be (15*7+5=110). next will be (16*7+5=117)

Sequence 103,110,117,124,......992,999

Last term=first term + (n-1)common difference

999=103+(n-1)7

999-103=(n-1)7

896/7=n-1

128+1=n

n=129.