Answer key · Set B
How Spread Out? Set B
18 The biggest is 11 and the smallest is 3. 11 − 3 = 8.
2The top set The top set runs from 1 to 14, a range of 13. The bottom set runs from 6 to 9, a range of 3.
37 The IQR is the third quartile less the first quartile: 15 − 8 = 7.
4True M has IQR 10 − 6 = 4. N has IQR 14 − 5 = 9. N is more spread out in the middle.
53 The median is 7. The lower half is 1, 2, 4, 5. Q1 is the middle of that half: between 2 and 4, so 3.
62, 3, 5, 8, 10 The median is 5. The lower half is 2, 3, 3, so Q1 = 3. The upper half is 6, 8, 10, so Q3 = 8.
71-C, 2-D, 3-B, 4-A Q1 and Q3 are middle numbers of the two halves. The range and the IQR are the distances.
81 The distances from 5 are 2, 0, 0 and 2. They add to 4, and 4 ÷ 4 = 1.
93, 1, 2, 4 Biggest less smallest.
1023 Range = biggest − smallest, so biggest = 8 + 15 = 23.
11False The IQR only covers the middle half, so it can never be longer than the whole spread from smallest to biggest.
12Your own words: a grown-up reads it.
Mark each answer, count the right ones and write the score on the sheet.