Final answer:
The question involves a ratio and a total number to find out how many celebrities joined last week. By converting the given ratio into whole numbers, we found that 20 out of 37 celebrities joined last week after calculating the value of one part in the ratio.
Step-by-step explanation:
The student is asking about how to determine the number of celebrities who joined an organization last week given a particular ratio and a total number.
The ratio of celebrities who joined last week to those who joined the week before is 5:4.25, and the total number of new celebrities over two weeks is 37. To solve this, we must first convert the ratio to fractions or whole numbers which can be managed more easily. The ratio can be simplified by multiplying both parts by 4 to get rid of the decimal, resulting in a ratio of 20:17.
Now we have whole numbers representing the ratio of last week's and the previous week's new celebrities, with a total of 20 + 17 = 37 parts. Next, we divide the total number of celebrities, 37, by the sum of the parts in the ratio, which gives us the value of one part. Then, we multiply the value of one part by the number of parts that represent last week's number of new celebrities.
Let's calculate the value of one part: 37 ÷ (20 + 17) = 37 ÷ 37 = 1. Hence, one part equals 1. The number of celebrities who joined last week (represented by 20 parts) is 20 × 1 = 20. Therefore, 20 new celebrities joined last week.