Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
Question
secondary 3 | A Maths
2 Answers Below
Anyone can contribute an answer, even non-tutors.
Averages
I got up to re arranging the formulas and substituting them but I don’t really know where to go from there and whether or not it was the right approach
See 2 Answers
Part i)
Average of 1st and 2nd = 72
So 1st + 2nd = 72 x 2 = 144
Average of 3rd and 4th = 77
So 3rd + 4th = 77 x 2 = 154
Average of 5th and 6th = 79
So 5th + 6th = 79 x 2 = 158
Total of 1st to 6th = 144 + 154 + 158 = 456
Overall Average = 456 ÷ 6 = 76
Part ii)
Average of 2nd and 3rd = 75
So 2nd + 3rd = 75 x 2 = 150
Average of 4th and 5th = 78
So 4th + 5th = 78 x 2 = 156
So 1st + 6th = Total - (2nd + 3rd) - (4th + 5th)
= 456 - 150 - 156 = 150
Average of the 1st and 6th = 150 ÷ 2 = 75