4.2 Presenting dataIB Maths: Applications and Interpretation HL: Mind map

Exam questions on 4.2 Presenting data

1. The masses, $m$ kg, of 50 parcels at a depot are recorded. $0<m\le2$: 4 parcels; $2<m\le4$: 11 parcels; $4<m\le6$: 17 parcels; $6<m\le8$: 12 parcels; $8<m\le10$: 6 parcels.
   Find the percentage of parcels with a mass greater than 8 kg.2 marks
2. The heights of 100 plants in a greenhouse are summarised by cumulative frequency. 8 plants have height at most 10 cm, 30 plants at most 20 cm, 68 plants at most 30 cm, 92 plants at most 40 cm and all 100 plants at most 50 cm. Assume that the cumulative frequency rises uniformly (in a straight line) between these heights.
   Estimate the number of plants with height between 15 cm and 35 cm.2 marks
3. Two cafés record the number of customers each day. Café A: minimum 35, lower quartile 48, median 60, upper quartile 72, maximum 91. Café B: minimum 30, lower quartile 50, median 58, upper quartile 66, maximum 110.
   Find the interquartile range (IQR) and the range of each café.3 marks