Free Fractions and Decimals Subjective Test 02 Practice Test - 7th grade
Question 1
If a number is multiplied by 16 and then divided by 5 the remainder would be zero. What is the least possible number? [1 MARK]
SOLUTION
Solution :Answer: 1 Mark
Let the number be xGiven x×165 = 1
Hence, x = 30
The least value of the number is 30
Question 2
Karan covers 3.2 km in 16 seconds. How far can Karan run in 1 minute? Express it in metres. [2 MARKS]
SOLUTION
Solution :Steps: 1 Mark
Answer: 1 Mark
3.2 km = 3200 metres
Given thatDistance covered in 16 seconds = 3200 metres
Distance covered in 1 second = (3200÷16)
= 200 metres.
1 minute = 60 seconds
Distance covered in 1 minute =60×200
=12000m
The distance covered in 1 minute is 12000 metres.
Question 3
Arrange the following in descending order.
(i) 23,421,79
(ii) 45,67,13
[2 MARKS]
SOLUTION
Solution : Each option: 1 Mark
Now, 79,23,421
The LCM of the denominators of the above fractions = 63
⇒7×79×7, 2×213×21, 4×321×3
⇒4963, 4263, 1263
Hence, arranging in descending order we have
4963>4263>1263
i.e., 79>23>421
(ii) The LCM of the denominators of the given fractions = 105
Making them like fractions. We have,
1×353×35, 4×215×21, 6×157×15
35105, 84105, 90105
⇒67>45>13
Question 4
Express 3460 grams in kilograms.
Now express 1712 kg in grams. [2 MARKS]
SOLUTION
Solution :In kilograms: 1 Mark
In grams: 1 Mark
1 Kilogram = 1000 grams
Or 1 gram=11000 kilograms
Let x kilograms = 3460 g
=(34601000) kilograms
= 3.460 kilograms
3460 grams = 3.460 kilograms
Now 1712 kg=17×2+12
=34+12
=352 kg
=352×1000 gms
=(35×500) gm
=17500 gms
Question 5
Kartik ate 35 part of an apple and Bharat ate the remaining part of the apple. What fraction of the apple did Bharat eat? Who had the larger share and by how much? [2 MARKS]
SOLUTION
Solution : Each answer: 1 Mark
Given that:
Fraction of the apple Kartik ate =35
Fraction of the apple uneaten =1−35
=5−35
=25
This part was eaten by his brother Bharath
∴ Bharath ate 25th part of the apple.
Comparing two fractions we have
35&25
Clearly 35>25
⇒ Karthik had the larger share which was larger by 35−25=15.
Question 6
How much less is 18km compared to 29000 metres ? [3 MARKS]
SOLUTION
Solution :Conversion Formula: 1 Mark
Steps: 1 Mark
Answer: 1 Mark
We know that
1 km=1000 m
Converting kilometers into meters
we have
18 km = 18×1000=18000 metresDifference = 29000-18000
=11000 metres
Or
29000 metres= 29 km
Difference = 29-18
=11 km
Question 7
Given that length of a side of an equilateral triangle is 3.4m. Find its perimeter in cm? [3 MARKS]
SOLUTION
Solution :Conversion Formula: 1 Mark
Steps: 1 Mark
Answer: 1 Mark
In an equilateral triangle, all the sides are equal.Let the side of an equilateral triangle be= a cm where a= 3.4 m ( given)
Now Perimeter = a+ a+a=(3a) m
= (3)*(3.4)
=10.2m
Hence perimeter of the equilateral triangle = 10.2m.
Now, 1 m= 100cm
∴ 10.2m=10.2×100 = 1020 cm.
Hence, the perimeter of the triangle is 1020 cm.
Question 8
Mohan finished colouring a picture in 712 hour. Keerthi finished colouring the same picture in 34 hour. Who worked longer? By what fraction was it longer? [3 MARKS]
SOLUTION
Solution : Steps: 2 Mark
Answer: 1 Mark
Given that
Mohan finishes the work in 712 of an hour.
Also given that
Keerthi finishes the work in 34 of an hour.
Now, 712 of an hour
⇒712×60 minutes
⇒35 mins
Again
34 of an hour
⇒34×60
⇒45 minutes
Clearly, Keerthi worked more by 45 - 35 = 10 more minutes.
Now, when expressed as a fraction
1060=16 of an hour.
Alternative Way
Method II
Now, 712 and 34
Making them Like fractions we have
7×112×1 & 3×34×3
i.e. 712<912
Clearly, Keerthi who takes 34th of an hour takes longer than Mohan who takes 712th of an hour.
So, subtracting we have
912−712=212=16 of an hour.
Question 9
In cricket, run rate is defined as the number of runs scored divided by the number of overs bowled. Team 'A' scores 260 runs in 50 overs batting first. The other team batting second scores at half the run rate of the team batting first and plays entire 50 overs. How many runs did the team batting second score? [3 MARKS]
SOLUTION
Solution :Steps: 1 Mark
Application: 1 Mark
Answer: 1 Mark
Given that
Team 'A' scored 260 runs in 50 overs.
So, run rate of the team batting first =(260/50)= 5.2 runs per over
The team batting second scored at half the run rate of the team batting firstRun rate of team the batting second
= (5.2/2)= 2.6 runs per over
Runs scored by the team batting second
=(50)×(2.6)= 130
Hence, the team batting second scored 130 runs.
Question 10
A circle is divided into 8 equal parts. Given that the area of the shaded portion is 104 m2. Find the area of the unshaded part of the circle.
[4 MARKS]
SOLUTION
Solution :Steps: 2 Marks
Application: 1 Mark
Result: 1 Mark
Given that
Area of the shaded portion = 104 m2The circle is divided into 8 equal parts
Area of the circle = (8)×104
= 20 m2
Area of unshaded part = Total area - shaded area
= 20 - 104 m2
= 80−104m2
= 704 = 17.5 m2
Hence, area of the unshaded portion is 17.5 m2
Question 11
Express (0.8×0.7)−(0.65×0.6)(0.65×0.6)−(0.62×0.6) in the form of a fraction.
[4 MARKS]
SOLUTION
Solution :Bodmas operation: 1 Mark
Simplifying the numerator and the denominator: 1 Mark
Answer: 2 Marks
Multiply and divide the equation by 100
=(8×7)−(6.5×6)(6.5×6)−(6.2×6)
=(56−39)(39−37.2)
=171.8
=17018
=859
Question 12
Anubha's father weighs 91 kg. Anubha's mother is 5 times Anubha's dog's weight. If Anubha's dog weighs 17 of Anubha's father's weight, find Anubha's mother's weight. [4 MARKS]
SOLUTION
Solution : Steps: 2 Mark
Application: 1 Mark
Answer: 1 Mark
Given that
Anubha's father weighs 91 kg.
Anubha's dog's weight=17 of Anubha's father's weight
⇒17×91
⇒917⇒13 kg
Also given
Anubha's mother's weight= 5 times Anubha's dog's weight
=5×13=65 kg
∴ Anubha's mother weighs 65 kg.
Question 13
Add the following decimals and then express it as a fraction.
7.205, 8.012, 3.1, 4.9, 27.3, 3.0009, 8.0102. [4 MARKS]
SOLUTION
Solution : Making them into like decimals: 1 Mark
Mathematical operation: 1 Mark
Fraction expression: 2 Marks
Now converting the decimals given into like decimals and adding it.
0– 7. 2 0 5 0–
0– 8. 0 1 2 0–
0– 3. 1 0– 0– 0–
0– 4. 9 0– 0– 0–
2 7. 3 0– 0– 0–
0– 3. 0 0 0 9
0– 8. 0 1 0 2
We get 6 1. 4 2 8 1
(II) Now, 61. 4281 can be rounded up
to 61.428
to 61. 43
to 61. 4
Now
61.4=61.4÷2100÷2=30750=6750
Question 14
(a) It is said that the weight of a body on the moon is 16th of its weight on earth. Calculate the weight of a car on the moon if it weighs 420 kg on Earth.
[4 MARKS]
(b) What is the fraction of coloured squares to the total number of squares? State your answer in decimals also.
SOLUTION
Solution : Each part: 2 Marks
(a)
Now, the weight of the car in Moon = 16 of its weight on earth.
⇒16 of 420 kg
⇒4206
⇒70 kg
∴ weight of the car in Moon = 70 kg only.
(b) There are 100 squares. 46 out of them are coloured. This picture shows forty-six hundredths.
To write 46 hundredths as a decimal, we use a place value chart.
The answer is 0.46.
Question 15
Car A covers 5.5 km in 4 litres of petrol and another car B covers 1800 metres in 1 litre of petrol. Calculate the mileage per litre of petrol and now calculate which car travels more and by how much distance compared to the other? [4 MARKS]
SOLUTION
Solution :Conversion Formula: 1 Mark
Steps: 2 Marks
Answer: 1 Mark
Given that
Distance covered by car A in 4 liters of petrol is 5.5 km.
Now 1 km=1000 m.
5.5 km=5500 mDistance covered by car A in 1 litre of petrol = (5500/4) = 1375 metres
Distance covered by car B in 1 liter of petrol = 1800 meters
So car B travels more compared to car A
Difference = 1800-1375 = 425 metres
Car B travels 425 meters more than car A