Basic Numeracy
BNU1501
Department of Decision Sciences
Assignment 1 Semester 2
Due Date: 15 August 2017
Unique Number: 761232
Before answering the assignment questions, please work through the
following study material:
• Chapters 1, 2 and 3 in the study guide
Question 1:
Round 13,4099 off to three decimal digits.
[1] 13,500
[2] 13,419
[3] 14,409
[4] 13,410
Answer:
To round 13,4099 off to three decimal digits, we look at the fourth decimal digit. In this case the
fourth digit is 9, which is not less than 5. Therefore, the digit in front of it, namely 9, will increase by
one in the rounding.
Thus 13,4099 = 13,410 rounded to three decimal digits.
Question 2:
Round 13,4099 off to two decimal digits.
[1] 13,41
[2] 14,40
[3] 13,49
[4] 13,50
Answer:
To round 13,4099 off to two decimal digits, we look at the third decimal digit. In this case it is the
number 9, which is not less than 5. Therefore, the digit in front of it, namely 0, will increase by one in
the rounding.
,Thus 13,4099 = 13,41 rounded to two decimal digits.
Question 3:
Round 13,4099 off to an integer.
[1] 14
[2] 134 099
[3] 13
[4] 14,4099
Answer:
To round 13,4099 off to an integer, we look at the first decimal digit. In this case it is the number 4,
which is less than 5. Therefore, the digit in front of it, namely 3, will not be influenced in the
rounding.
Thus 13,4099 = 13 rounded to an integer.
Question 4:
A father is 3 years younger than 5 times his son’s age. Suppose the son is 𝑥 years old. Give an
expression in 𝑥 for the father’s age.
[1] 3 + 5𝑥
[2] 3𝑥 + 5
[3] 5𝑥 − 3
[4] 3𝑥 − 5
Answer:
The son is 𝑥 years old.
Five times the son’s age is 5 × 𝑥 = 5𝑥 years.
Therefore, the father is (5𝑥 − 3) years old.
Question 5:
Steward cycles at an average speed of 10 kilometres per hour. How many days will it take him to
travel 1 000 kilometres, if he cannot cycle more than 8 hours per day?
[1] 12,5 days
[2] 100 days
[3] 150 days
[4] 80 days
Answer:
In 1 hour, Steward travels 10 kilometres.
Therefore, in 8 hours, he travels 10 × 8 = 80 kilometres.
To travel 1 000 kilometres will take Steward:
, 1 000
80
12,5 days
Question 6:
A school bought 500 tables for the grade 11 and 12 learners. 𝑠 of them were Samsung tablets at
1 000 apiece and the rest were Ipads at R1 200 apiece. An expression, in terms of 𝑠, for the number
of Ipads bought is…
[1] 200𝑠
[2] 500 − 𝑠
[3] 500 + 𝑠
[4] 𝑠 − 500
Answer:
There were 500 tablets in total. 𝑠 of them were Samsung tablets. Thus, (500 − 𝑠) were Ipads.
Question 7:
Refer to question 6 above. How much in terms of 𝑠 do all the Ipads cost the school?
[1] 10 000(200𝑠) rand
[2] (500 + 𝑠)1 200 rand
[3] 1 200(500 − 𝑠) rand
[4] (𝑠 − 500)1 000 rand
Answer:
One Ipad costs R1 200.
Two Ipad’s cost 𝑅1 200 × 𝑅2
Thus, (500 − 𝑠) Ipads cost
1 200 × (500 − 𝑠)
= 1 200 (500 − 𝑠) rand
Question 8:
Alexander travels 𝑥 kilometre in 𝑝 hours at a certain average speed. An expression for the average
speed at which Alexander travels is…
[1] 𝑥𝑝 km/h
𝑥
[2] 𝑝
km/h
[3] (𝑥 − 𝑝) km/h
𝑝
[4] 𝑥
km/h
Answer:
To find Alexander’s average speed, we want to know how far he travels in one hour.
Now, in 𝑝 hours, he travels 𝑥 kilometres.
BNU1501
Department of Decision Sciences
Assignment 1 Semester 2
Due Date: 15 August 2017
Unique Number: 761232
Before answering the assignment questions, please work through the
following study material:
• Chapters 1, 2 and 3 in the study guide
Question 1:
Round 13,4099 off to three decimal digits.
[1] 13,500
[2] 13,419
[3] 14,409
[4] 13,410
Answer:
To round 13,4099 off to three decimal digits, we look at the fourth decimal digit. In this case the
fourth digit is 9, which is not less than 5. Therefore, the digit in front of it, namely 9, will increase by
one in the rounding.
Thus 13,4099 = 13,410 rounded to three decimal digits.
Question 2:
Round 13,4099 off to two decimal digits.
[1] 13,41
[2] 14,40
[3] 13,49
[4] 13,50
Answer:
To round 13,4099 off to two decimal digits, we look at the third decimal digit. In this case it is the
number 9, which is not less than 5. Therefore, the digit in front of it, namely 0, will increase by one in
the rounding.
,Thus 13,4099 = 13,41 rounded to two decimal digits.
Question 3:
Round 13,4099 off to an integer.
[1] 14
[2] 134 099
[3] 13
[4] 14,4099
Answer:
To round 13,4099 off to an integer, we look at the first decimal digit. In this case it is the number 4,
which is less than 5. Therefore, the digit in front of it, namely 3, will not be influenced in the
rounding.
Thus 13,4099 = 13 rounded to an integer.
Question 4:
A father is 3 years younger than 5 times his son’s age. Suppose the son is 𝑥 years old. Give an
expression in 𝑥 for the father’s age.
[1] 3 + 5𝑥
[2] 3𝑥 + 5
[3] 5𝑥 − 3
[4] 3𝑥 − 5
Answer:
The son is 𝑥 years old.
Five times the son’s age is 5 × 𝑥 = 5𝑥 years.
Therefore, the father is (5𝑥 − 3) years old.
Question 5:
Steward cycles at an average speed of 10 kilometres per hour. How many days will it take him to
travel 1 000 kilometres, if he cannot cycle more than 8 hours per day?
[1] 12,5 days
[2] 100 days
[3] 150 days
[4] 80 days
Answer:
In 1 hour, Steward travels 10 kilometres.
Therefore, in 8 hours, he travels 10 × 8 = 80 kilometres.
To travel 1 000 kilometres will take Steward:
, 1 000
80
12,5 days
Question 6:
A school bought 500 tables for the grade 11 and 12 learners. 𝑠 of them were Samsung tablets at
1 000 apiece and the rest were Ipads at R1 200 apiece. An expression, in terms of 𝑠, for the number
of Ipads bought is…
[1] 200𝑠
[2] 500 − 𝑠
[3] 500 + 𝑠
[4] 𝑠 − 500
Answer:
There were 500 tablets in total. 𝑠 of them were Samsung tablets. Thus, (500 − 𝑠) were Ipads.
Question 7:
Refer to question 6 above. How much in terms of 𝑠 do all the Ipads cost the school?
[1] 10 000(200𝑠) rand
[2] (500 + 𝑠)1 200 rand
[3] 1 200(500 − 𝑠) rand
[4] (𝑠 − 500)1 000 rand
Answer:
One Ipad costs R1 200.
Two Ipad’s cost 𝑅1 200 × 𝑅2
Thus, (500 − 𝑠) Ipads cost
1 200 × (500 − 𝑠)
= 1 200 (500 − 𝑠) rand
Question 8:
Alexander travels 𝑥 kilometre in 𝑝 hours at a certain average speed. An expression for the average
speed at which Alexander travels is…
[1] 𝑥𝑝 km/h
𝑥
[2] 𝑝
km/h
[3] (𝑥 − 𝑝) km/h
𝑝
[4] 𝑥
km/h
Answer:
To find Alexander’s average speed, we want to know how far he travels in one hour.
Now, in 𝑝 hours, he travels 𝑥 kilometres.
