Which of the following statements is/are TRUE about prime numbers?
i) The sum of all the factors of a prime number is more than the number itself.
ii) The sum of two prime numbers is a multiple of 2.
iii) 2 is a prime number.
(1 Point)
i and ii
ii and iii
i and iii
all the above
Answers
Answer:
Ncert solutions
Grade 6
Mathematics
Chapters in NCERT Solutions - Mathematics, Class 6
Exercises in Playing With Numbers
Question 4
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.
Solution
Transcript
SOLUTION:
i) false because there are plenty of numbers that are divisible by 3 but not divisible by 9. eg.30.
ii) true
iii) false, number 30 for example, is divisible by 3 and 6 but not divisible by 18.
iv) true
v) false, we know that two numbers having only 1 as a common factor are called co.prime numbers, so not necessary that one of them must be prime.
vi) false, example number 36 is divisible by 4 but not divisible by 8.
vii) true
viii) true
ix) false, example number 5 exactly divides the sum of two number 2 and 3 but not exactly divide these two numbers.
all the above...
the three Statement that are given above is true.