Final answer:
Out of the additional 15 friends Gertrude surveys, b) 6 of them will prefer soccer.
Step-by-step explanation:
To find out how many of the additional 15 friends will prefer soccer, we can use the ratio of the students who preferred soccer in the initial survey. Out of 25 friends, 10 preferred soccer, which can be written as a ratio of 10/25. We can use this ratio to find out how many of the additional 15 friends will prefer soccer.
By setting up a proportion, we can solve for x, the number of additional friends who will prefer soccer.
10/25 = x/15
Cross-multiplying, we get:
25x = 10 * 15
25x = 150
x = 150/25
x = 6
Therefore, out of the additional 15 friends, b)6 of them will prefer soccer.