Proportions
"Chime" for solving proportions
Cross multiply, divide by the other guy
How do you find the area of a parallelogram?
base times height
What is one of the formulas for finding the area of a triangle?
A = 1/2bh or A = bh/2
Solve: 50 x 42
2100
Which unit goes in the numerator to set up fractions?
The unit you're solving for
How do you correctly label your final answers for the area of a parallelogram?
unit squared, or unit2
Why do we multiply by 1/2 or divide by 2 in the formula for the area of a triangle?
Because a triangle is always half of a parallelogram.
Solve: (4 x 6) / 2
or 1/2(4)(6)
12
Solve: 30 miles to 2 cm equals how many miles to 5 cm?
75cm
Find the area of a parallelogram with a base of 8cm and a height of 15cm.
120 cm2
Find the area of a triangle with a base of 15m and a height 5m.
A=75m2
Solve the Proportion:
25/4 = 50/x
x = 8
If you have a scale of 2 feet for every inch, how many feet is 10 inches?
20 ft
A parallelogram has the following dimensions:
base = 3in, side length = 7in, and height = 6 in.
Find the area.
18 in2
A triangle has a height of 26yd, a base of 13 yd, and a side length of 34yd. What is the area?
A=338yd2
Solve: (5.3 x 4)(3.8 x 4)
322.24
If you have a scale of 2 in to every 500 feet, what is the scale factor in feet to inches?
250 ft/in
If a rectangle has two side lengths of 23.5mm, and two side lengths of 12.4mm, what is the area of the rectangle?
A=291.4mm2
If the area of a triangle equals 40cm2, and has a height of 10cm, what was the length of the base?
b = 8cm
Find the scale factor for:
10:6
1 2/3 or 5/3