CBSE Class 6 Maths - Playing With Numbers - NCERT Exercise 3.5 (#cbsenotes)

Playing With Numbers

EXERCISE 3.5

CBSE Class 6 Maths

Q1: Which of the following statements are true?
(a) If a number is divisible by 3, it must be divisible by 9.
(b) If a number is divisible by 9, it must be divisible by 3.
(c) A number is divisible by 18, if it is divisible by both 3 and 6.
(d) If a number is divisible by 9 and 10 both, then it must be divisible by 90.
(e) If two numbers are co-primes, at least one of them must be prime.
(f) All numbers which are divisible by 4 must also be divisible by 8.
(g) All numbers which are divisible by 8 must also be divisible by 4.
(h) If a number exactly divides two numbers separately, it must exactly divide their sum.
(i) If a number exactly divides the sum of two numbers, it must exactly divide the two numbers separately.


Answer:
(a) ✗ (e.g. 15 is divisible by 3 but not by 9)
(b) ✔
(c) ✔
(d) ✔
(e) ✗ (e.g. 8 and 9 are co-primes and none of these are prime. )
(f) ✗
(g) ✔
(h) ✔
(i) ✗


Q2: Here are two different factor trees for 60. Write the missing numbers.

CBSE Class 9 - Science - Unit Test Paper (2017-18) (#cbsepapers)

CBSE Class 9 - Science Unit  Test Paper (2017-18)

Chapters Covered In Unit Paper:
   1. Straight Line Motion
   2. Cell - Fundamental Unit Of Life
   3. Matter and Its Surroundings

CBSE Class 11/12, AIPMT/NEET - Biology - List of Important Proteins and Their Occurrence (#cbsenotes)(#biologynotes)

List of Important Proteins and Their Occurrence

Protein	Found Where
Albumin	Egg White, Milk, Blood Plasma
Actin	Muscle Fibres (Contractile protein)
Collagen	Tendon, Bones
Casein	Milk, Egg Yolk
Keratin	Hair, Horn, feathers, Nail
Cytochrome	Mitochondria
Elastin	Arteries, Ligaments,Yellow Fibres

CBSE Class 6 Maths - Playing With Numbers - NCERT Exercise 3.4 (#cbsenotes)

Playing With Numbers

EXERCISE 3.4

CBSE Class 6 Maths

Q1: Find the common factors of :
(a) 20 and 28 
(b) 15 and 25
(c) 35 and 50 
(d) 56 and 120

Answer:
(a) Factors of 20 = 1, 2, 4, 5, 10, 20
Factors of 28 = 1, 2, 4, 7, 14, 28
Common factors = 1, 2, 4

(b) Factors of 15 = 1, 3, 5, 15
Factors of 25 = 1, 5, 25
Common factors = 1, 5

(c) Factors of 35 = 1, 5, 7, 35
Factors of 50 = 1, 2, 5, 10, 25, 50
Common factors = 1, 5

(d) Factors of 56 = 1, 2, 4, 7, 8, 14, 28, 56
Factors of 120 = 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 60, 120
Common factors = 1, 2, 4, 8

CBSE NEET/AIPMT Class 12 Biology - Animal Nutrition and Digestive System (MCQs) (#cbsenotes)

Animal Nutrition and Digestive System 

(Biology MCQs) For NEET, Pre-Medical and AIPMT  

Q1 (AIPMT 2014): An alga which can be employed as food for human being is _______.

(a) Ulothrix
(b) Spirogyra
(c) Chlorella
(d) Polysiphonia


Q2: Carrier ions like Na⁺ facilitate the absorption of which of the following substances:

(a) glucouse and fatty acids
(b) amino acids and glucouse
(c) glycerol and fatty acids
(d) fructose and some amino acids


Q3: Which of the following food components reach totally undigested in human stomach?

(a) Protein and Starch
(b) Starch and Fat
(c) Fat and Cellulose
(d) Starch and Cellulose

CBSE Class 9 - Maths - Number Systems - Important Points To Remember (#cbsenotes)

Number Systems

CBSE Class 9 Maths 

Important Points To Remember

① Counting numbers 1, 2, 3, 4... are called Natural Numbers (N)


② Whole Numbers (W): Natural numbers 1, 2, 3... together with number 0 (zero) are called Whole Numbers


③ All natural numbers, zero and negative numbers together i.e. ...., –4, –3, –2, –1, 0, 1, 2, 3, 4, ... are known as Integers (Z).


④ Rational Numbers (Q): Numbers of the form p/q where p, q both are integers and q ≠ 0.

CBSE Class 10 - Chemistry - Chapter 1 - Chemical Reactions and Equations (#cbsenotes)

Chemical Reactions and Equations 

CBSE Class 10 - Chemistry - Chapter 1 

Worksheet on Balancing Chemical Equations

Question: Balance the following chemical equations.

⒜ Al(s) + Fe₂O₃(s) ---⤑  Al₂O₃(s) + Fe(s)

⒝ Na(s) + H₂O ---⤑ NaOH + H₂

⒞ NH₃(g) + O₂(g) ---⤑ NO(g) + H₂O(g)

⒟ Fe(s) + H₂O(g) ---⤑  Fe₃O₄(s) + H₂(g)

⒠ NaOH + H₂SO₄ ---⤑  Na₂SO₄ + H₂O

⒡ Hg(NO₃)₂ + KI ---⤑ HgI₂ + KNO₃