Final answer:
The percent increase in the billing rate is calculated by dividing the change in the rate ($18) by the original rate ($150) and converting it to a percentage, resulting in a 12% increase.
Step-by-step explanation:
The question involves calculating the percent increase in the billing rate of a software company's consultants. To find the percentage increase, we take the difference between the new rate and the original rate and then divide that by the original rate. This gives us the ratio of the increase to the original amount, which we can then convert into a percentage.
The original rate was $150 per hour, and the new rate was $168 per hour. The change in rate is therefore $168 - $150, which equals $18. To find the percent increase, we divide the change by the original rate: $18 / $150 = 0.12. Converting this to a percentage, we multiply by 100 and get 12%, which is option A) 12%.