AISS Prelim EMath Paper 1 Marking Scheme

3 AISS PRELIM/4052/01/2025 [Turn over Answer all the questions. 1 Expand and simplify 225 3 5pqpqr . 32 26 2 10 15 5 25pp qp rp q q q r Answer ...…………….……………. [2] 2 Lee has two pieces of string. Their lengths are in the ratio 5 : 3 and the total length of the two pieces of string is 8 x cm. Lee cuts 6 cm from each piece of string. The ratio of their lengths is now 9 : 5. Find the value of x. the first piece of string be 5x cm. The first piece of string is 5x cm. The second piece of string is 3x cm. 56 9 36 5 25 30 27 54 24 2 12 x x xx x x Answer x =…………….…………… [3] 3 A salesperson earns a fixed weekly salary of $1000 plus 8% commission on the total value of items he sells. (a) In one week, he sold items worth $1750. Calculate the total amount the salesperson earned that week. Total amount = $1000 + 8 1750100u = $1140 Answer $...…………….…………… [1] B1 B2 if all terms are correct B1 if at least 3 terms are right M1 for setting up the right equation M1 for manipulation of algebraic terms A1

4 AISS PRELIM/4052/01/2025 (b) The following week, the salesperson earned a total of $1450. Calculate the total value of items he sold that week. Commission = $1450 $1000 = $450 8% represents $450 100% represents $ 450 1008 u = $5625 4 The box-and-whisker-plot gives information about the time, in hours, that 120 adults spent on social media in one week. (a) State the median time. 15.5 hours Answer ………………………..hours [1] (b) State the range. Range = 31.5 6.5 = 25 Answer ………………………. hours [1] (c) There was an error in the collection of data. Every adult spent 2 hours less on social media in one week. Describe the effect this change would have on the box-and-whisker plot. The whole box-and-whisker plot will move to the left by 4 square units. M1 for recognising that 8% rep $450 B1 B1 all key words must be present A1 B1

5 AISS PRELIM/4052/01/2025 [Turn over 5 6 Sketch the graph of 83yx x on the axes below. Indicate clearly the values where the graph crosses the x- and y- axes. [3] Express as a single fraction in its simplest form 45 32 3 yy . 45 32 3 4 1 21 51 0 32 3 14 3 32 3 yy yy yy y yy

Answer ...…………….…………… [2] M1 for combining to a single fraction A1 B1 correct shape and y-intercept B1 correct turning point B1 correct x-intercepts Coor of turning point (2.5, 30.25)

6 AISS PRELIM/4052/01/2025 7 (a) A map has a scale of 1