In a given year, about 1.52×10^10 pieces of first-class mail are delivered in the U.S. If each piece of mail carries a stamp costing $0.55, what is the total cost in dollars to deliver all the pieces? Write the answer in scientific notation, expressed to the exact decimal place.

Answer 1

To find the total cost of delivering all the pieces of first-class mail, we multiply the number of pieces of mail by the cost of each stamp.

The number of pieces of first-class mail is given as: \[ 1.52 \times 10^{10} \]

The cost of each stamp is: \[ 0.55 \text{ dollars} \]

Now, we calculate the total cost: \[ \text{Total Cost} = (1.52 \times 10^{10}) \times 0.55 \]

Calculating \( 1.52 \times 0.55 \): \[ 1.52 \times 0.55 = 0.836 \]

Next, we need to consider that we are multiplying by \( 10^{10} \): \[ 0.836 \times 10^{10} \]

To express it in proper scientific notation, we can rewrite \( 0.836 \) as \( 8.36 \times 10^{-1} \): \[ 0.836 \times 10^{10} = 8.36 \times 10^{-1} \times 10^{10} = 8.36 \times 10^{9} \]

Thus, the total cost in scientific notation is: \[ \boxed{8.36 \times 10^{9}} \]