➻ In a group of 40 people, 27 can speak English and 25 can speak Spanish.
➻ The required number of people who can speak both English and Spanish .
<u>Consider</u> ,
➻ A → Set of people who speak English.
➻ B → Set of people who speak Spanish
➻ A∩B → Set of people who can speak both English and Spanish
➻ n(A∪B) = n(A) + n (B) - n(A∩B)
➻ 40 = 27 + 25 - n (A∩B)
➻ 40 = 52 - n (A∩B)
➻ n (A∩B) = 52 - 40
➻ ∴ n (A∩B) = 12
∴ Required Number of persons who can speak both English and Spanish are <u>12 .</u>
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➻ n(A∪B) = n(A) + n (B) - n(A∩B)
➻ 40 = 27 + 25 - 12
➻ 40 = 52 - 12
➻ 40 = 40
➻ ∴ L.H.S = R.H.S
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Answer:
The COP is 0.5
Step-by-step explanation:
First we must find the slopes.
12.50/25 = 0.5
17.50/35 = 0.5
The COP is 0.5
Question 1:
For this case, the first thing we must do is define variables.
We have then:
x: number of nickels
y: number of dimes
We write the system of equations that adapts to the problem.
We have then:
0.05x + 0.10y = 6.10
x + y = 67
Solving the system we have:
x = 12
y = 55
Answer:
there are 12 nickels
Question 2:
For this case, the first thing we must do is define variables.
We have then:
x: Allan's score
y: Dave's score
We write the system of equations that adapts to the problem.
We have then:
x + y = 375
x = 2y-60
Solving the system we have:
x = 230
y = 145
Answer:
Dave: 145 Allan: 230
Are you asking for the expression?
If so, you plug into the format (x - h)² + (y - k)² = r² where (h, k) is the center and r is the radius.
(x + 2.5)² + (y + 4.4)² = (7/4)²
Simplify to get your equation and answer:
(x + 2.5)² + (y + 4.4)² = 49/16