Answer:
$106.67
Step-by-step explanation:
Using the example, for 3 hours work, Alex would be paid ...
(2 hr)($30/hr) +(1 hr)($20/hr) = $60 +$20 = $80
At the same rate of pay, for 4 hours work, the pay would be ...
pay/(4 hr) = $80/(3 hr)
pay = $80(4/3) ≈ $106.67
Alex's pay for 4 hours of work is $106.67.