Express 42 and 100 as the sum of two consecutive primes.

Write the smallest and the biggest two digit prime number.

The sum of any three odd natural numbers is odd. Justify this statement with an example.

Find the prime factorisation of each number by factor tree method and division method. 
a) 60 
b) 128 
c) 144 
d) 198 
e) 420 
f) 999

Find the HCF of each set of numbers using prime factorisation method.
(i) 18, 24   (ii) 51, 85    (iii) 61, 76     (iv) 84, 120    (v) 27, 45, 81     (vi) 45, 55, 95

Find the HCF and the LCM of the numbers 154, 198 and 286.

Is 173 a prime? Why?

The sum of three prime numbers is 80. The difference of two of them is 4. Find the numbers.

Find the smallest number which is exactly divisible by all the numbers from 1 to 9.

Convert 526 ml into l

A bag contains 81 kg of sugar. If the shopkeeper fill up these into small packets of 750 g each, then how many packets can be made from 81 kg of sugar?

Calculate the duration of time
(i) from 5.30 a.m to 12.40 p.m
(ii) from 1.30 p.m to 10.25 p.m
(iii) from 20:00 hours to 4:00 hours
(iv) from 17:00 hours to 5:15 hours

Two pipes whose lengths are 7 m 25 cm and 8 m 13 cm joined by welding and then a small piece 60 cm is cut from the whole. What is the remaining length of the pipe?

Put mark in the circles which adds upto the given measure.

1.	1 Kg	500 g	50 g	100 g	200 g	250 g
2.	1 m	10 cm	30 cm	40 cm	25 cm	5 cm
3.	1 l	200 ml	100 ml	50 ml	500 ml	200 ml

A room has a door whose measures are 1 m wide and 2 m 50 cm high.
i. Can we take a bed of 2 m and 20 cm length and 90 cm wide into the room.?

Seetha wakes up at 5.20 a.m. She spends 35 minutes to get ready and travels 15 minutes to reach the railway station. If the train departs exactly at 6:00 a.m, will Seetha catch the train?

Valavan bought 24 eggs for Rs. 96. Four of them were broken and also he had a loss of Rs. 36 on selling them. What is the selling price of one egg?

Nathan paid Rs. 800 and bought 10 bottles of honey from a village vendor. He sold them in a city for Rs. 100 per bottle. Find his profit or loss.

A fruit seller bought 2 dozen bananas at Rs. 20 a dozen and sold them at Rs. 3 per banana. Find his gain or loss.

A vegetable vendor buys 10 kg of tomatoes per day at Rs. 10 per kg, for the first three days of a week. 1 kg of tomatoes got smashed on everyday for those 3 days. For the remaining 4 days of the week he buys 15 kg of tomatoes daily at Rs. 8 per kg. If for entire week he sells tomatoes at Rs. 20 per kg, then find his profit or loss for the week.

In \(\Delta\)ABC, name the
a) Three sides: ______ , ______ , _______
b) Three Angles: ______ , ______ , _______
c) Three Vertices: ______ , _______ , _______

Classify the given triangles based on its angles as acute angled, right angled or obtuse angled.

I am a closed figure with each of my three angles is 60°. Who am I?

If one angle of an isosceles triangle is 124°, then find the other angles.

Which of the following statements is true? Why?
(a) Every equilateral triangle is an isosceles triangle.
(b) Every isosceles triangle is an equilateral triangle.