Identifying the standard method a problem needs

Name:

Date:

Class:

Quick Questions

Shade in the A or B circle for each question.

1. A problem says: 'Add up the prices of all 30 items in a basket.' Which standard method does it need?

A Totalling

B Counting

2. A problem says: 'Find how many students scored above 50.' Which standard method does it need?

A Totalling

B Counting

3. A problem says: 'Output the highest temperature recorded in a week.' Which method does it need?

A Finding the maximum

B Finding the minimum

4. Which key word tells you a problem needs a calculation of the average?

A 'mean' or 'average' mark

B 'lowest' mark

5. A problem says: 'Check whether the name Zoe is in a list of 20 names.' Which method does it need?

A Bubble sort

B Linear search

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1Total ← Total + Mark		AMatches problems with key words like 'how many': use counting
2Count ← Count + 1		BIF Score > Max THEN Max ← Score
3A problem asking for the 'highest' score needs the maximum method		C'Put in order' is a key phrase for sorting, not searching. It needs a bubble sort.
4A problem that says 'put in order' needs a bubble sort		D'How many' is a key phrase for counting, not totalling. It should use Count ← Count + 1.
5'How many students passed?' → Total ← Total + Mark		EMatches problems with key words like 'add up' or 'sum': use totalling
6'Put the marks in order' → linear search		FIF Marks[i] > Marks[i + 1] THEN swap

Definitions

key words

Fill in the Blanks

Complete each line of code by filling in the missing parts.

// add up all the marks Total ← Total _ Mark

// how many students scored over 50 Count ← Count + _

IF Mark _ Lowest THEN Lowest ← Mark ENDIF

// find a mark in the list Found ← _____ FOR Index ← 1 TO 10

// put the marks in order IF Marks[I] > Marks[I + 1] THEN ____ ← Marks[I]

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A // Add up all the prices

B Total ← 0

C FOR i ← 1 TO 10

D Total ← Total + 1

E NEXT i

Question 2

A // Problem: highest mark

B // Method: totalling

C Max ← Mark[1]

Question 3

A // How many pupils passed

B IF Mark >= 50 THEN

C Count ← Count + Mark

D ENDIF

Question 4

A // Highest of 10 marks

B // Step 1: total the marks

C // Step 2: divide by count

Question 5

A // Find a name in a list

B // Method: bubble sort

C Found ← FALSE

Answer Key

Identifying the standard method a problem needs

Section A: Quick Questions

A — Totalling

B — Counting

A — Finding the maximum

A — 'mean' or 'average' mark

B — Linear search

Section B: Match the Pairs

Total ← Total + Mark → Matches problems with key words like 'add up' or 'sum': use totalling

Count ← Count + 1 → Matches problems with key words like 'how many': use counting

A problem asking for the 'highest' score needs the maximum method → IF Score > Max THEN Max ← Score

A problem that says 'put in order' needs a bubble sort → IF Marks[i] > Marks[i + 1] THEN swap

'How many students passed?' → Total ← Total + Mark → 'How many' is a key phrase for counting, not totalling. It should use Count ← Count + 1.

'Put the marks in order' → linear search → 'Put in order' is a key phrase for sorting, not searching. It needs a bubble sort.

Section C: Definitions

key words — Words in a problem, like add up, how many, highest, average, find or put in order, that show which standard method to use: totalling, counting, max/min, average, search or sort.

Section D: Fill in the Blanks

// add up all the marks
Total ← Total + Mark

// how many students scored over 50
Count ← Count + 1

IF Mark < Lowest THEN
  Lowest ← Mark
ENDIF

// find a mark in the list
Found ← FALSE
FOR Index ← 1 TO 10

// put the marks in order
IF Marks[I] > Marks[I + 1] THEN
  Temp ← Marks[I]

Section E: Spot the Error

D — The key words 'add up' mean totalling, so each price must be added to Total. Adding 1 would count the items instead. It should be Total ← Total + Price[i].

B — The key word 'highest' points to the maximum method, which keeps the largest value seen so far. Totalling adds values together. It should be '// Method: maximum'.

C — 'How many' means counting, so Count must go up by 1 each time the condition is true. Adding Mark would total the marks. It should be Count ← Count + 1.

A — The steps total the marks and then divide, which is the average method. The key word in the problem should be 'average', not 'highest'. It should be '// Average of 10 marks'.

B — The key word 'find' means searching for an item, so the method is linear search. Bubble sort puts items in order. It should be '// Method: linear search'.