Question
The length of a tangent from a point A at a distance 5
cms. from the centre of the circle is 4 cms. Radius of the circle isSolution
A tangent at any point of a circle is perpendicular to the radius through the point of contact. Therefore, ∠OTA = 90° and ΔOTA is a right-angled triangle. By Pythagoras theorem, OA2 = OT2 + AT2 52 = OT2 + 42 OT2 = 25 - 16 OT2 = 9 OT = ± 3 Radius OT cannot be negative. Hence, the radius is 3 cm.
Average 20 numbers is ‘x’. If the average of first 12 numbers is 72.5 while average of last 5 numbers is 82.2 and 13th, 14th a...
The average of 8 numbers is 12. If the 2 is added in 1st number, 4 is added in 2nd number, 8 is added in 3rd number and in the same way the number are a...
- The average of 36 values is 92. What will be the average if every value is multiplied by 9?
There are five containers in a truck hold. The weight of the first container is 100 kg and the weight of the second container is 20% higher than the wei...
- The average of two numbers is 3 more than the smaller number among them. If the greater number is 25% more than the smaller number, then find the sum of th...
Find the mean of the following observations:
45, 54, 42, 56, 46, 48, 52, 50, 57, 43Find the average of the numbers 12, 14, 18 and 26
A batsman scores 87 runs in the 21st match of his career. His average runs per match increases by 2. What was his average before the 21st match.
5 positive numbers are written on a piece of paper. Sum of first 3 numbers is 60 and ratio of the 4th and the 5th number is 2:3. If difference between t...
Average age of A, B and C is 20 years. Average age of B and C was 12 years when A was born. If B is 21 years old, then, find the age of C, 6 years hence.