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2 years ago

Kevin is 3 years older than brendon two years ago Kevin was 4 times as old as brendon . How old is Kevin now

Mathematics

1 answer:

Tpy6a [65]2 years ago

4 0

Answer:

Kevin is 6

Step-by-step explanation:

Let k represent Kevin's age now. Then Brendon's age now is (k-3). Two years ago the relationship of their ages was ...

k-2 = 4((k-3) -2)

k -2 = 4k -20 . . . . . eliminate parentheses, collect terms

3k = 18 . . . . . . . . . . add 20-k

k = 6 . . . . . . . . . . . . divide by 3

Kevin is 6 now.

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A group of freshmen at a local university consider joining the equestrian team. Thirty‑five percent of students choose Western r

lesantik [10]

Answer:

a) Option D) 0.75

b) Option D) 0.3

Step-by-step explanation:

We are given the following in the question:

Percentage of students who choose Western riding = 35%

$P(w) = 0.35$

Percentage of students who choose dressage= 45%

$P(d) = 0.45$

Percentage of students who choose jumping = 50%

$P(j) = 0.50$

Percentage of students who choose both dressage and jumping = 20%

$P(d \cap j) = 0.20$

Percentage of students who choose Western and dressage = 10%

$P(w \cap d) = 0.10$

Percentage of students who choose Western and jumping = 0%

$P(w \cap j) = 0$

Thus, we can say

$P(w \cap j \cap d) = 0$

Formula:

$P(A \cup B) = P(A) + P(B) - P(A \cap B)$

a) P(student chooses dressage or jumping)

$P(d \cup j) = P(d) + P(j) -p(d \cap j)\\= 0.45 + 0.50-0.20 = 0.75$

b) P(student chooses neither dressage nor Western riding)

$= 1 - P(d \cup w)\\= 1 - (P(d) + P(w) - P(d \cap w))\\= 1 - (0.45 + 0.35 - 0.10)= 0.3$

5 0

3 years ago

4x + 9y = 4

saw5 [17]

Answer:

x=101/65, y=-16/65. (101/65, -16/65).

Step-by-step explanation:

4x+9y=4

9x+4y=13

----------------

9(4x+9y)=9(4)

-4(9x+4y)=-4(13)

------------------------

36x+81y=36

-36x-16y=-52

----------------------

65y=-16

y=-16/65

4x+9(-16/65)=4

4x-144/65=4

4x=4+144/65

4x=404/65

x=(404/65)/4=101/65

x=101/65, y=-16/65.

7 0

2 years ago

The number of goals scored by a soccer team varies directly as the number of shots on goal. If the Lakeside Bears scored 4 goals

enot [183]

Since it varies directly, divide the number of shots by the number of goals:

48 shots / 4 goals = 12

This tells you they score a goal every 12 shots.

Multiply shots needed by number of goals:

12 x 3 = 36

They need 36 more shots to score 3 more goals.

6 0

2 years ago

Caroline baked 3 dozen oatmeal raisin cookies for the bake sale at school this is 1/4 the number of dozens of cookies she baked

anyanavicka [17]

144 is how much cookies she baked

7 0

2 years ago

What is the solution of the matrix equation?

katrin [286]

Hello from MrBillDoesMath!

Answer:

The first choice ( -12, 20)

Discussion:

Using matrix multiplication we find the equations:

1x + 1y = 8 (A)

2x + 3y = 36 (B)

Next, compute

2(A) - B =>

(2x + 2y) - (2x + 3y) = 2*8 - 36 =>

(2x - 2x) + ( 2y-3y) = 16 - 36 =>

-y = -20 =>

y = 20

Substituting this y value in (A) gives

x + 20 = 8 =>

x = 8 - 20 =>

x = -12

The answer is the first choice ( -12, 20)

Thank you,

MrB

6 0

2 years ago