Final answer:
The percent of change in Rachel's pay from 2019 to 2020 is calculated by subtracting her old wage from her new wage, then dividing by the old wage and multiplying by 100. The change in her wage was $4.50 per hour, leading to a percentage change of approximately 42.86%.
Step-by-step explanation:
Rachel's pay per hour increased from $10.50 in 2019 to $15.00 in 2020. To find the percent of change in her pay, we calculate the increase in salary and then divide it by the original salary amount for 2019. The formula used is: Percentage change = (Change in quantity ÷ Original quantity) × 100.
The increase in pay is $15.00 - $10.50 = $4.50. Thus, the percentage increase in Rachel's pay is ($4.50 ÷ $10.50) × 100, which equals approximately 42.86%. Hence, the percent of change in Rachel's pay from 2019 to 2020 is 42.86%.