REAL data type
Name:
Date:
Class:
A
Quick Questions
Shade in the A or B circle for each question.
1. Which value is a REAL literal in Cambridge pseudocode?
2. Which data type should you choose for TotalToPay, which holds 12.50 (money)?
3. Which literal is REAL?
4. Which is the correct way to write a REAL value of three tenths?
5. Which is the correct way to write a REAL value of four?
B
Match the Pairs
Draw a line connecting each item on the left to its match on the right.
| Left column | Right column | |
|---|---|---|
| 1DECLARE TotalToPay : REAL | AA REAL must have a digit after the decimal point, so 12. is invalid. It should be 12.0. | |
| 2Height ← 0.3 | BCount ← 5 Length ← 5.0 | |
| 35 is an INTEGER because it has no decimal point, but 5.0 is a REAL | CTemperature ← -4.0 | |
| 4A negative REAL still has a digit on each side of the point, even when its fractional part is zero | DA REAL must have a digit before the decimal point, so .5 is invalid. It should be 0.5. | |
| 5Price ← .5 | ECreates a variable that can store a number with a fractional part, such as a price | |
| 6TotalToPay ← 12. | FAssigns a REAL literal with a digit on each side of the point |
C
Definitions
REAL
D
Fill in the Blanks
Complete each line of code by filling in the missing parts.
1.
DECLARE Price : ____
Price ← 4.7
2.
_______ Height : REAL
Height ← 1.5
3.
DECLARE Distance : REAL
Distance ← ___ // five as a REAL value
4.
DECLARE __________ : REAL
TotalToPay ← 12.5
5.
DECLARE Count : _______
Count ← 5
E
Spot the Error
Shade in the letter of the line that contains an error.
Question 1
A
DECLARE Price : REAL
B
Price ← .7
C
OUTPUT Price
Question 2
A
DECLARE Height : INTEGER
B
Height ← 1.75
C
OUTPUT Height
Question 3
A
DECLARE TotalToPay : REAL
B
TotalToPay ← 0.0
C
TotalToPay ← 9,99
D
OUTPUT TotalToPay
Question 4
A
DECLARE Temp : REAL
B
Temp ← 21.5
C
Temp ← -4.
D
OUTPUT Temp
Question 5
A
DECLARE Mass : REAL
B
DECLARE Count : INTEGER
C
Count ← 5.0
D
OUTPUT Count
Answer Key
REAL data type
Section A: Quick Questions
Q1
A — 4.7
Q2
B — REAL
Q3
A — 5.0
Q4
B — 0.3
Q5
A — 4.0
Section B: Match the Pairs
Q1
DECLARE TotalToPay : REAL → Creates a variable that can store a number with a fractional part, such as a price
Q2
Height ← 0.3 → Assigns a REAL literal with a digit on each side of the point
Q3
5 is an INTEGER because it has no decimal point, but 5.0 is a REAL → Count ← 5
Length ← 5.0
Q4
A negative REAL still has a digit on each side of the point, even when its fractional part is zero → Temperature ← -4.0
Q5
Price ← .5 → A REAL must have a digit before the decimal point, so .5 is invalid. It should be 0.5.
Q6
TotalToPay ← 12. → A REAL must have a digit after the decimal point, so 12. is invalid. It should be 12.0.
Section C: Definitions
Q1
REAL — The data type for a number that can have a fractional part, written with a digit on each side of the point, such as 4.7 or 0.3. 5 is an INTEGER but 5.0 is REAL.Section D: Fill in the Blanks
Q1
DECLARE Price : REAL
Price ← 4.7Q2
DECLARE Height : REAL
Height ← 1.5Q3
DECLARE Distance : REAL
Distance ← 5.0 // five as a REAL valueQ4
DECLARE TotalToPay : REAL
TotalToPay ← 12.5Q5
DECLARE Count : INTEGER
Count ← 5Section E: Spot the Error
Q1
B — A REAL literal needs at least one digit on each side of the decimal point. .7 should be written 0.7.
Q2
A — Height stores 1.75, which has a fractional part. An INTEGER cannot hold it, so the variable must be declared as REAL.
Q3
C — A REAL literal uses a decimal point, not a comma. It should be 9.99.
Q4
C — A REAL literal needs a digit after the decimal point as well as before it. -4. should be -4.0.
Q5
C — 5.0 is a REAL value, but Count is an INTEGER. The whole number 5 must be assigned instead.