Screenshot below-mathematics ,help please!!

(a) range = difference between highest

mark and lowest mark

range of marks = 10 - 6

= 4

(b) total students = marks × frequency

(6×5)+(7×4)+(8×7)+(9×10)+(10×4)

= 30+28+56+90+40

= 244 students

(c) total frequency = 5+4+7+10+4

= 30

mean mark = total students/total

frequency

= 244/30

= 8.133

example 2 – simplify: step 1: completely factor both the numerators and denominators of all fractions. step 2: change the division sign to a multiplication sign and flip (or reciprocate) the fraction after the division sign; essential you need to multiply by the reciprocal. step 3 : cancel or reduce the fractions.

x = -4

step-by-step explanation:

- 20 - 4(x + 3) = 4x

=> -20 - 4x - 12 = 4x

=> - 32 -4x = 4x

=> -32 = 4x + 4x

=> - 32 = 8x

=> -32/8 = x

=> -4 = x