Scale Drawings
A map scale is 1in to 8mi. Two towns are 2.25in apart on the map. What is the actual distance?
18 miles
If y=kx, and y=21 when x=7, find k and y when x=3
k=3
y=9
Find the radius of a circle when the diameter is 50cm.
25cm
What is 15% of 200?
30
Solve
5/6-1/3
5/6-2/6=3/6=1/2
A model house is built at 1:50 scale. If a real room is 5m long, how long is the model room in centimeters?
5 m ÷ 50 = 0.1 m = 10 cm
A pack of 4 batteries costs $3.60. What is the unit price per battery?
$0.90
Find the circumference of a circle with diameter 12 cm.
C=37.68cm
A $80 jacket is marked 30% off. What is the sale price?
Discount=$24
Sale price=$56
Solve
(-7) + 4 + 10
7
A scale drawing uses 1cm:5m. A rectangle in the drawing is 6cm by 4cm. What are the actual dimensions in meters?
30m by 20m
A graph through (0,0) and (6,15) shows a proportional relationship. What is the constant of proportionality?
k=15/6
Find the area of a circle with a radius of 9cm.
254.34 sq. cm.
A population grows from 1,250 to 1,375. What is the percent increase?
Increase Amount=125
Percent Increase = (125/1,250) × 100% = 10%.
Solve
-2/3*9/4
-18/12=-3/2
An original painting is 24in by 18in. A reproduction is made at a scale factor of 0.25. What are the reproduction's dimensions?
6in by 4.5in
Two quantities, a and b, are proportional. When a=14, b=35. Find b when a=9.
b=2.5 × 9=22.5
A circle's circumference is 75.36 cm. What is its diameter?
2πr = 75.36cm
radius = 12cm
diameter = 24cm
A $150 gadget is discounted 20% and then a further 10% off the sale price. What is the final price?
After first discount: 150 × 0.8=$120.
After second discount: 120 × 0.9=$108
Solve
7div(-1/7)
-49
In a scale drawing of a playground, a rectangular sandbox measures 3in by 2in. The scale is 1in=6ft. What is the actual perimeter in feet?
Actual dimensions: 18ft by 12ft.
Perimeter=2(18+12)=60 ft
A car uses 6 liters of gas for every 45 miles. How many liters does it use for 300 miles?
300 × 2/15=40 liters
Find the radius of a circle whose area is 78.5 sq. m.
A=pir^2
78.5divpi=25
sqrt(25)=5
A number is increased by 18% to become 236. What was the original number?
236 ÷ 1.18=200
Solve and simplify the answer.
-3/4+5/6-1/12
Common Denominator: 12
(-9+10-1)/12=0/12=0