In an examination, Dada scored x% in Maths, 50% in Science and 70% in English Studies. If his mean score for the three subjects was 55%, find x.

45% she scored in maths

Step-by-step explanation:

To find the mean of any set of numbers you have to add the the numbers and divide by how many numbers. So if your mean for the three subjects is 55% then we can form the equation (x+50+70) / 3 = 55. All you have to do here is simply solve: x+50+70 = 165, and then x = 165-120 = 45 %

4 and 5)16.97 or 12√2

6)15.59 or 9√3

7)y = 15.59 or 9√3     x =27

8)17.80