Differences Of Squares
a2-4
(a-2)(a+2)
sqrt(64)
8
Three coins are tossed. What is the probability of getting at most two heads?
A. 3/4
B. 1/4
C. 3/8
D. 7/8
D. 7/8
1000
1x103
In the dog park there is 60 male dogs and 20 female dogs,What is the ratio of male to female dogs?
3/1
1-49c2
(1-7c)(1+7c)
sqrt(144)
12
What is the probability of getting a sum 9 from two throws of a dice?
A. 1/6
B. 1/8
C. 1/9
D. 1/12
C. 1/9
676,000,000,000
6.76 x1011
A jar is filled with pennies and nickels in the ratio of 5 to 3 (pennies to nickels). There are 30 nickles in the jar, how many coins are there?
80 Coins
36-n2
(6-n)(6+n)
sqrt(196)
14
In a box, there are 8 red, 7 blue and 6 green balls. One ball is picked up randomly. What is the probability that it is neither red nor green?
A. 1/3
B. 3/4
C. 7/19
D. 8/21
A. 1/3
0.00000078
7.8 x10-7
The measures of the two acute angles of a right triangle are in the ratio 2:7. What are the measures of the two angles?
2x = 2 × 10 = 20°
7x = 7 × 10 = 70°
144-9f2
(12-3f)(12+3f)
sqrt(289)
17
A bag contains 2 red, 3 green and 2 blue balls. Two balls are drawn at random. What is the probability that none of the balls drawn is blue?
A. 10/21
B. 11/21
C. 2/7
D. 5/7
A. 10/21
7,000,000,000
7 x109
There are 600 pupils in a school. The ratio of boys to girls in this school is 3:5. How many girls and how many boys are in this school?
375 Girls
5c3-4d2
Prime
sqrt(361)
19
Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5?
A. 1/2
B. 2/5
C. 8/15
D. 9/20
A. 1/2
39,900,000,000,000
3.99 x1013
The angles of a triangle are in the ratio 1:3:8. Find the measures of the three angles of this triangle.
x = 15°
3x = 3 × 15 = 45°
8x = 8 × 15 = 120°