Q 1. If 
, then x =
(a) 15
(b) 21
(c) – 15
(d) – 21
Given,
-3/7=x/35
Also given, we have to find the value of x.
According,
-3/7=x/35
=> x= (-3×37) / 7
=> x= -15
Q 2. A rational number is a number that can be put in the form P/q where p and q are:
(a) natural numbers and q ≠ 0
(b) whole numbers and q ≠ 0
(c) non-negative integers and q ≠ 0
(d) integers and q ≠ 0
(d) integers and q ≠ 0
Q 3. A fraction is a rational number, and a rational number:
(a) can never be a fraction.
(b) may or may not be a fraction.
(c) is also a fraction.
(d) can always be reduced to a fraction.
(b) may or may not be a fraction.
Q 4. Rakesh has 10 one rupee coins of similar kind. He puts them exactly one on the other. What shape will he get finally?
(a) circle
(b) Cylinder
(c) Cube
(d) cone
(b) Cylinder
Q 5. Adjoining figure is
(a) Cone
(b) Square pyramid
(c) Prism
(d) Triangular pyramid
(d) Triangular pyramid
Q 6. There are ________ vertices in a cube.
(a) 8
(b) 6
(c) 4
(d) none of these
(a) 8
Q 7. What cross-section do you get when you give a horizontal cut to a round apple?
(a) Circle
(b) Square
(c) Rectangle
(d) Triangle
(a) Circle
Q 8. Match the following appropriate solids:.
Q 8. Fill in the blanks:
- A square pyramid has ……………… faces.
- A prism has ……………… edges.
- The solid ……………… has no edges and no vertices.
- The numbers ________ and ________ are their own reciprocals.
- Between any two distinct rational numbers there are ___________ rational numbers.
- Two rational numbers are equal if they have the same __________ form.
- 5
- 9
- Sphere
- – 1 & 1
- infinite
- simplest
Q 10. Write each of the following numbers with positive denominator is 12/ -17
12/ -17
To write it in positive denominator form we have to multiply and divide the same number with
Q 11. Express 42/- 63 as a rational numbers with denominator 3 .
=> -42/63 (or) 42/(-63)
=> -42/(21×3)
=> –2/3
Q 12. Arrange the rational numbers -7/10, 5/8, 2/3 in ascending order.
We first write the given rational numbers so that their denominators are positive.
We have
Thus, the given rational numbers with positive denominators are
Now, LCM of the denominators 10, 8 and 3 is 2 2 5 3 3 = 120
We now write the numbers so that they have a common denominators 120 as Follows:
– 84 < – 80 < – 75
Q 13. Separate positive and negative rational numbers from the following rational numbers:
Given (-5/-7), (12/-5), (7/4), (13/-9), 0, (-18/-7), (-95/116), (-1/-9)
A rational number is said to be positive if its numerator and denominator are either positive integers or both negative integers.
Therefore positive rational numbers are: (-5/-7), (-18/-7), (7/4), (-1/-9)
A rational number is said to be negative integers if its numerator and denominator are such that one of them is positive integer and another one is a negative integer.
Therefore negative rational numbers are: (12/-5), (13/-9), (-95/116)
Q 14. Which of the two rational numbers -4/9 and 5/-12 is greater ?
Q 15. If three cubes of dimensions 2 cm × 2 cm × 2 cm are placed end to end, what would be the dimension of the resulting cuboid?
Length of the resulting cuboid = 2 cm + 2 cm + 2 cm = 6 cm
Breadth = 2 cm
Height = 2 cm
Hence the required dimensions = 6 cm × 2 cm × 2 cm.
Q 16. Give three example from our daliy life which are in the form of
(i) a cone
(ii) a Sphere
(iii) a Cuboid
(iv) a cylinder
(v) a pyaramid
Q 17. A bag contains lemon flavoured candies only. Shalini takes out one candy without looking into the bag. What is the probability that she takes out an orange flavoured candy?
The bag contains only lemon flavored candies, and nothing else.
There are no orange flavored candies in the bag. Hence there is no possibility of taking out an orange candy.
Therefore, the probability of taking out an orange flavored candy =0
Q 18. Here is an incomplete net for making a cube. Complete it in at least two different ways. Remember that a cube has six faces. How many are there in the net here?’
These three faces are given.
Q 19. Find the product:
(i) 3/7 × 4/5
= (3 × 4)/(7 × 5)
= 12/35
(ii) 7/3 × 5/2
= (7 × 5)/(3 × 2)
= 35/6
(iii) 5 × 3/7
= 5/1 × 3/7
= (5 × 3)/(1 × 7)
= 15/7
Q 20. Simplify:
21.5÷5 – 1/5 of (20.5 5.5) + 0.5 × 8.5