Step-by-step explanation:
Count the number of times you have to move the decimal point to the right until it is to the right of the 1st nonzero number.
a) You have to move the decimal point 11 times until it gets to the right of the 1st nonzero number, which is 7. You then rewrite this number as

The exponent of 10 is a negative number because you moved the decimal point to the right.
b) Similarly, you have to move the point 9 times to the right so the answer is

Answer:
21,42,84,168,336,672, 1,344
Step-by-step explanation:
The pattern is to multiply the previous term by 2 to find the next term. The seventh term should be 1,344.
Answer :
no. of days used to repair 1250m of road = 5
no. of days used to repair 1m of road = 5/1250
no. of days used to repair 8000m of road (8*1000m ) = 5/1250*8000= 32 days