2.2 cubic dm of brass is to be drawn into a cylindrical wire of 0.25 cm in diameter. Find the length of the wire?
Given,
2.2 dm3 of brass is to be drawn into a cylindrical wire of Diameter = 0.25 cm
So, radius of the wire (r) = d/2
= 0.25/2 = 0.125*10-2 cm
Now, 1 cm = 0.01 m
So, 0.1cm = 0.001 m
Let the length of the wire be (h)
We know that,
Volume of the cylinder = pr2h
It’s understood that,
Volume of cylindrical wire = Volume of brass of 2.2 dm3

h = 448 m
Therefore, the length of the cylindrical wire drawn is 448 m
The cost of 40 meters of cloth is Rs 200. Find the cost of 50 meters of cloth.
Given cost of 40 meters of cloth = Rs 200
Cost of 1 meter of cloth = (200/40)
Therefore, the cost of 50 chocolates = (200/40) × 50
= Rs 250
A car can cover a distance of 522 km on 36 liters of petrol. How far can it travel on 14 liters of petrol?
Given that number of kilometres a car can cover by using 36 litres of petrol = 522 km
Number of kilometres a car can cover by using 1 litre of petrol = 522/36
Hence, the number of kilometres a car can cover by using 14 litres = (522/36) × 14
= 203 km
20 chocolates cost Rs 320. Find the cost of 35 such chocolates.
Given cost of 20 chocolates = Rs 320
Cost of 1 chocolate = (320/20)
Therefore, the cost of 35 chocolates = (320/20) × 35
= Rs 560
How many spherical bullets each of 5 cm in diameter can be cast from a rectangular block of metal 11dm x 1 m x 5 dm?
Given,
A metallic block of dimension 11dm x 1m x 5dm
The diameter of each bullet = 5 cm
We know that,
Volume of the sphere = 4/3 pr3
Since, 1 dm = 10-1m = 0.1 m
The volume of the rectangular block = 1.1 x 1 x 0.5 = 0.55 m3
Radius of the bullet = 5/2 = 2.5 cm
Let the number of bullets made from the rectangular block be n.
Then from the question,
The volume of the rectangular block = sum of the volumes of the n spherical bullets
0.55 = n x 4/3 p(2.5)3
Solving for n, we have
n = 8400
Therefore, 8400 can be cast from the rectangular block of metal.
Rammohan sir classes
Hello Kumar
Go my class >>search for ram mohan class or navidaya/Sainik exam 20 >> enroll full course
meaning of sexhttp://yuthhrhyt
it is a process by which any individual reproduce and give birth to their offsprings.
How many terms are there in the AP 41, 38, 35, …, 8?
Given: AP is 41, 38, 35,…, 8
Here, first term = a = 41
Last term = 8
Common difference = d = 38 – 41 = -3
To find: the number of terms (n)
Last term = a + (n – 1)d
8 = 41 + (n – 1)(-3)
8 – 41 = (n – 1)(-3)
n – 1 = 11
n = 11 + 1 = 12
There are 12 terms.
How many terms are there in the AP 6, 10, 14, 18, …. 174?
Given: AP is 6, 10, 14, 18,…, 174
Here, first term = a = 6
Common difference = d= 10 – 6 = 4
To find: the number of terms (n)
Last term = a + (n – 1)d
174 = 6 + (n – 1) 4
174 – 6 = (n – 1) 4
n – 1 = 168 /4 = 42
n = 42 + 1 = 43
There are 43 terms.
If the nth term of a progression is (4n – 10) show that it is an AP. Find its
(i) first term,
(ii) common difference, and
(iii) 16th term
nth term of AP is 4n – 10 (Given)
Putting n = 1, 2, 3, 4, …, we get
At n = 1: 4n – 10 = 4 x 1 – 10 = 4 – 10 = -6
At n = 2: 4n – 10 = 4 x 2 – 10 = 8 – 10 = -2
At n = 3: 4n – 10 = 4 x 3 – 10 = 12 – 10 = 2
At n = 1: 4n – 10 = 4 x 4 – 10 = 16 – 10 = 6
We see that -6, -2, 2, 6,… are in AP
(i) first term = -6
(ii) Common difference = -2 – (-6) = 4
(iii) 16th term:
Using formula: an = a + (n – 1)d
Here n = 16
a16 = -6 + (16 – 1)4 = 54