Question 1 Report
Below are the scores of a group of students in a test:
Scores123456No. of students1456x2 S c o r e s 1 2 3 4 5 6 No. of students 1 4 5 6 x 2
If the average scores is 3.5, find the value of x.
Answer Details
Scores123456No. of students1456x2 S c o r e s 1 2 3 4 5 6 No. of students 1 4 5 6 x 2 Average = 3.5 3.5 = (1×1)+(2×4)+(3×5)+(4×6)+5x+(6×2)1+4+5+6+x+2 ( 1 × 1 ) + ( 2 × 4 ) + ( 3 × 5 ) + ( 4 × 6 ) + 5 x + ( 6 × 2 ) 1 + 4 + 5 + 6 + x + 2 3.51 3.5 1 = 1+8+15+24+5x+1218+x 1 + 8 + 15 + 24 + 5 x + 12 18 + x 3.51 3.5 1 = 60+5x18+x 60 + 5 x 18 + x 60 + 5x = 3.5(18 ÷ ÷ x) 60 + 5x = = 63 + 1.5x 5x - 1.5x = 63 - 60 1.5x = 3 x = 31.5 3 1.5 3015 30 15 = 2