Class 10r sat a test.
the mean mark for the class was 70%.
there are 30 students in class 10r, 20 of whom are boys.
the mean mark for the boys in the test was 62%.
work out the mean mark for the girls.

i can you with this answer

step-by-step explanation:

step-by-step explanation:

for exempl this   system of equations   y = x - 3

                                                                y = 2x - 5

look   the line : y = x -3     ( red)

                            the line : y = 2x -5 ( bleus)