Question

If seven LEGO sets are sold each second, how many LEGO sets are sold in three hours?

Answer 1

See a solution process below:

Explanation:

There are: 60 minutes per hour.

And, there are 60 seconds per minutes.

So we can find the number of seconds in 3 hours as:

`3"hr" xx (60"min")/"hr" xx (60"sec")/"min" =>`

`3color(red)(cancel(color(black)("hr"))) xx (60color(blue)(cancel(color(black)("min"))))/color(red)(cancel(color(black)("hr"))) xx (60"sec")/color(blue)(cancel(color(black)("min"))) =>`

`3 xx 60 xx 60"sec" =>`

`180 xx 60"sec" =>`

`10800"sec"`

And if there 7 Lego sets sold every second we can multiply the seconds we calculated above by `7` to find the number of Lego sets sold over 3 hours:

`(7"sets")/"sec" xx 10800"sec" =>`

`(7"sets")/color(red)(cancel(color(black)("sec"))) xx 10800color(red)(cancel(color(black)("sec"))) =>`

`7"sets" xx 10800 =>`

`75600"sets"`

On average the are 75,600 Lego sets sold every 3 hours.