Answer:
4 hours
Explanation:
We know the following:
Total amount Randy earned: $667
Pay for first 40 hours: $14.50 per hour
Pay after 40 hours: $21.75 per hour
We need to find the total extra hours:
![x](https://img.qammunity.org/2021/formulas/mathematics/middle-school/p9sq9b3rc5nwoqzhzc8wcaj51b36281l9g.png)
If the total number of hours worked are,
, then:
![x + 40 = T](https://img.qammunity.org/2021/formulas/mathematics/middle-school/dokpfrzscadul3y23j1nbql9yjh58sg0n0.png)
Total pay received for the first 40 hours:
![40 * 14.50 = 580](https://img.qammunity.org/2021/formulas/mathematics/middle-school/wbhxcqsfgfigeqfr4fal1khz8bjgkgrb34.png)
If out of $667, Randy earns $580 from the first 40 hours, the left over are earned by extra hours.
$667 - $580 = $87 ------- (a)
Total pay received for working after 40 hours:
![21.75x](https://img.qammunity.org/2021/formulas/mathematics/middle-school/3k5e4dxsbxm6tz9u7o02p805g0d8432g00.png)
We know from eq (a) that total pay is 87, hence we can find the number of hours using this.
![21.75x = 87\\\\x = (87)/(21.75)\\\\x = 4](https://img.qammunity.org/2021/formulas/mathematics/middle-school/bgaziuxk1odg7y9ghr9mtory6746rlvto3.png)
Randy worked 4 extra hours.