Final answer:
The sales lady's commission rate is calculated by dividing the commission earned by the value of goods sold eligible for commission. Her commission was 2000 shillings for goods worth 40,000 shillings, leading to a commission rate of 5%, which is not listed in the options provided.
Step-by-step explanation:
The question involves a sales lady whose earnings are based on a basic salary plus a commission for sales above a certain amount. She earns a basic salary of 5000 shillings and sold goods worth 70,000 shillings in one month. Given that her total earnings were 7000 shillings, we need to find the percentage of commission she receives on the sales above 30,000 shillings.
First, we calculate the total commission earned by subtracting the basic salary from the total amount earned: 7000 shillings - 5000 shillings = 2000 shillings. This 2000 shillings is the commission on the sales above 30,000 shillings.
Next, we find out the value of goods sold that is eligible for commission: 70,000 shillings - 30,000 shillings = 40,000 shillings.
Now, we calculate the commission rate by dividing the commission earned by the value of goods sold eligible for commission and then multiplying by 100 to get the percentage: (2000 shillings / 40,000 shillings) * 100 = 5%. However, this percentage is not one of the options, which suggests there might have been a mistake in the survey of options provided or the total amount received by the sales lady.