7th Grade Math

Test PracticeT

Probability

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434 Probability and Predictions

Geometric probability deals with the areas of figures instead of the number

of outcomes. For example, the probability of landing in a specific region of a

target is the ratio of the area of the specific region to the area of the target.

P(specific region) =

area of a specific region

__

area of the target

Find the probability that the point of a pin dropped on the board will

land within the shaded region. Write as a fraction in simplest form.

P(shaded region) =

area of shaded region

__

area of the target

= _^1525 or _^35

39. Find the probability that a randomly dropped pin will land with the
    point in the shaded region of each board. Write as a fraction in simplest
    form.
    a.
    b.
    c.


40. A bag contains 8 blue marbles, 15 red
    marbles, 10 yellow marbles, and 3 brown
    marbles. If a marble is randomly selected,
    what is the probability that it will be
    brown?
    A. 0.27 C. 0.08
    −
    3
    B. 22% D. _^3
    8


41. The records of a sporting goods store
    show that 1 out of every 4 balls
    purchased is a football. What is the
    probability that a football will NOT be
    purchased when a ball is purchased?
    F. ^1
    1
    H. ^3
    4
    G. ^1
    4
    I. ^1
    25


42. What is the

76

0 2

3 4

1 5

2

probability of the

spinner landing on a

number less than 3?

A. 25% C. 50%

B. 37.5% D. 75%

38. The desserts at a picnic include 8 ice
    cream sandwiches, 9 chocolate frozen
    bananas, 12 ice cream cones, 11 frozen
    pops, 16 push-up sticks, and 14 shaved
    ice cones. What is the probability of
    choosing an ice cream cone at random?
    F. ^6
    29
    H. ^1
    6
    G. ^6
    35
    I. ^1
    12

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