Question

The US postal service delivered 7.14 x 1010 pieces of mail in the month of December and 3.21 x 1010 in the month of January. What is the total mail delivered for these two months? A) 1.035 x 109 B) 1.035 x 1010 C) 1.035 x 10-10 D) 1.035 x 1011

Answer 1

The correct option is:  D) $1.035 \times 10^1^1$

Explanation

Number of mails delivered in the month of December $=7.14 \times 10^1^0$

and number of mails delivered in the month of January $= 3.21\times 10^1^0$

For finding the total number of mails delivered for these two months, we need to add $7.14 \times 10^1^0$ and $3.21\times 10^1^0$

$(7.14 \times 10^1^0)+(3.21\times 10^1^0)\\ \\ = (7.14+3.21)\times 10^1^0\\ \\ = 10.35\times 10^1^0\\ \\ =\frac{10.35}{10}\times 10^1^1 = 1.035 \times 10^1^1$

So, the total mail delivered for these two months is $1.035 \times 10^1^1$

Answer 2

D) 1.035*10^11 

Hope this helps