Part A.
7.8 is a rational number between 7.7 and 7.9.
It is rational because it can be written as a fraction of integers, such as 78/10.
Part B.
sqrt(60) = 7.75
sqrt(60) cannot be written as a fraction of integers. It is a decimal number that never ends and never repeats.
A sideways opening parabola is in the form

, so we know from the process of elimination that it will either be b or c. Next we have to realize that if the parabola opens to the left it is a negative parabola, just like if a parabola opens upside down it is a negative parabola. So the one that has the negative out front is b.
8m(4+7p). (The greatest common factor is 8.).
Answer: There are 20 girls who preferred insta.
Step-by-step explanation:
Since we have given that
Total number of students who were surveyed = 100
Number of boys who preferred insta among 50 boys = 40
Number of girls who preferred snpchat among 50 girls = 30
We need to find the number of girls who preferred insta.
So, Number of girls who preferred insta = Total number of girls - Number of girls who preferred snpchat.

Hence, there are 20 girls who preferred insta.