This pseudocode algorithm is intended to allow, at random, between 1 and 20 values to be entered and totalled. The total and average of the entered values are output at the end of the algorithm. 01 DECLARE Loop : STRING 02 DECLARE Limit : INTEGER 03 DECLARE Value : REAL 04 DECLARE Total : REAL 05 Total ← 0 06 Limit ← ROUND(RANDOM() * 19,0) + 1 07 IF Loop ← 1 TO Limit 08 OUTPUT "Enter a number" 09 INPUT Loop 10 Total ← Total * Value 11 NEXT Loop 12 OUTPUT "The total of the numbers entered is ", Total 13 OUTPUT "The average of the numbers entered is ", Total / Limit

Mark scheme

Marking points from the official mark scheme (May/June 2024). The mark or mark type is shown in brackets.

1. [4] (a) One mark per mark point • Line 01 / DECLARE Loop : STRING should be DECLARE Loop : INTEGER • Line 07/ IF Loop ← 1 TO Limit should be FOR Loop ← 1 TO Limit • Line 09 / INPUT Loop should be INPUT Value • Line 10/Total ← Total * Value should be Total ← Total + Value Correct algorithm: 01 DECLARE Loop : INTEGER 02 DECLARE Limit : INTEGER 03 DECLARE Value : REAL 04 DECLARE Total : REAL 05 Total ← 0 06 Limit ← ROUND(RANDOM() * 19,0) + 1 07 FOR Loop ← 1 TO Limit 08 OUTPUT "Enter a number" 09 INPUT Value 10 Total ← Total + Value 11 NEXT Loop 12 OUTPUT "The total of the numbers entered is ", Total 13 OUTPUT "The average number entered is ", Total / Limit
2. [2] (b) One mark per mark point • Correct use of ROUND with 2 arguments separated by comma, for example ROUND( 5, 2) (in statement 13) ... • (Total / Limit,1) correct arguments For example: OUTPUT "The average of the numbers entered is ", ROUND (Total / Limit,1)
3. [4] (c) One mark per mark point, max four • After line 09 / after the input • Insert a WHILE / pre-condition loop... • to check if the value entered is between 1 and 500 inclusive If the value is not in range, output an error message • and insert another input statement for re-input. Or • Before line 08 / before the input message start a REPEAT / post-condition loop After line 09 / after the input close the REPEAT loop by checking if the value entered was between 1 and 500 inclusive If it wasn't, (the loop will repeat) for the number to be re-input / If it was, the program continues.