Question

You buy 30 of your favorite songs from a Web site that charges ​$0.98 for each song. What is the cost of 30 ​songs? Use mental math.

Answer 1

If you are going to use mental math, round $0.98 up to $1.

Rounded, the cost of the 30 songs is $30.

However, since you rounded at the beginning, you need to subtract 2 cents for every song you purchased from the total of $30.

Multiply 30 by $0.02 to get $0.60. Subtract $0.60 from $30.

Your answer should be $29.40.

Answer 2

$29.40

Explanation:

When we use mental math to calculate, we simplify the values to calculate them easily.

Since a website that charges $0.98 for each songs rounded to $1.00

You buy 30 of your favorite songs = 30 × 1

= $30.00

Now subtract 2 cents × 30 = 60 cents or $0.60

$30.00 - 0.60

= $29.40

The cost of 30 songs is $29.40