The diameter of a ring is 19mm. Calculate the area of the ring in cm^2, giving the area to 3 significant figures.
First you must convert the diameter into cm from mm:19/10 = 1.9cmThen you must find the radius of the ring:radius = diameter/2 = 1.9/2 = 0.95 cmThen you can calculate the area:area = 2πr2 = 2 x π x (0.95)2 = 5.67 cm2
MP
Related Maths GCSE answers
All answers ▸If the hypotenuse of a triangle is 7cm and another side is 4cm, what's the length of the other side? How can I work this out?
S is a geometric sequence. a) Given that (√x - 1), 1, and (√x + 1) are the first three terms of S, find the value of x. b) Show that the 5th term of S is 7 + 5√2
A ladder 6·8m long is leaning against a wall, as shown in the diagram. The foot of the ladder is 1·5m from the wall. Calculate the distance the ladder reaches up the wall. Give your answer to a sensible degree of accuracy.
How do you complete the square?