Formulas
This is the formula for the area of what shape?
A = 1/2 b*h
A triangle
If a rectangle has a base of 20 cm and a height of 7 cm, what is the area of the rectangle?
20cm x 7cm = 140 cm2
A sheet of paper that is 11 inches long has an area of 93.5 square inches. What is the width of the paper?
8 inches.
What country was Pythagoras from?
Greece
This is the formula for the area of what shape?
A=1/2*d1*d2
A kite
If a triangle is 5 meters wide and 6 meters tall, what is the area?
A = 1/2 * 5 * 6 = 1/2(30) = 15 m2
What is the radius of a circle with an area of 64pi?
8
What letter is contained in the spelling of every odd number?
What is the formula for the area of an annulus?
A = pi*(R2 - r2)
What is the area of an annulus with an outer radius of 6 in. and an inner radius of 3 in.? (in terms of pi)
A = pi*(62 - 32) = (36 - 9)pi = 27pi
If a kite has an area of 37 square inches, and one diagonal measures 14 inches, what is the length of the other diagonal? Round to 2 decimal places.
6.17 inches
What number is approximately 22/7?
pi
What formula would you use to find the area of the white boards in this classroom?
A = bh (or A = lw)
If each large white board is 4ft by 8ft, what is the total area of the large white boards in this classroom?
What is the circumference of a circle with radius 64pi?
16pi
What is the one-billionth digit of pi?
9
Describe in words how to find the area of a sector of a circle.
Find the area of the circle, and multiply by the fraction representing the arc that describes the sector.
Gino's pizza cuts a large pizza into 10 slices. If the radius of the pizza is 8 inches, what is the area of one slice of pizza? (round to 2 decimal places)
A square and a circle each have a perimeter (or circumference) of 50 inches. Which has the greater area?
Circle
What is the world record for the time it takes to count to one billion?
89 days (Jeremy Harper, 2007)