L'età media di Aldo, Bruno, Carlo e Davide è 16 anni. Se non si tiene conto di Davide, l'età media dei tre rimanenti sale a 18.
1 answer:
Answer:
Davide's age is 10.
L'età di Davide è 10.
Step-by-step explanation:
The average age of Aldo, Bruno, Carlo and Davide is 16 years.
I am going to say that:
x is Aldo's age.
y is Bruno's age.
z is Carlo's age.
w is Davide's age.
Average of the 4 is 16 years.
This means that:
If we do not consider Davide, the mean is 18. So
Replacing in the first equation:
Davide's age is 10.
L'età di Davide è 10.
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Answer:
ft/min is the rate of changing of width
Step-by-step explanation:
Given -
The area always remain constant i.2 2 square feet.
Height of the rectangle = 2 feet
Rate of changing of height = 6 feet per minute
Since area is constant
2 sq ft = (2 * 6) ft/min * 1 * x ft/min
x = ft/min
Question:
In triangle FGH, FG = 12.3 cm, GH = 10.6 cm, m angle G=80 degrees, and m angle H=55 degrees. If triangle ABC GHF, which statement is true?
(A) AB = 12.3 cm
(B) AB = 10.6 cm
(C) m∠C = 55°
(D) m∠C = 80°
Answer:
Option B:
AB = 10.6 cm
Solution:
The image of the triangle is attached below.
In ΔFGH,
FG = 12.3 cm, GH = 10.6 cm, m∠G = 80° and m∠H = 55°
Option A: AB = 12.3 cm
Given ΔGHF ΔABC.
Corresponding parts of congruence triangles are congruent.
GH = AB = 10.6 cm
So, option A is not true.
Option B: AB = 10.6 cm
Already proved in option A that AB = 10.6 cm
So, option B is true.
Option C: m∠C = 55°
ΔGHF ΔABC
Corresponding parts of congruence triangles are congruent.
m∠G = m∠A = 80°
m∠H = m∠B = 55°
Sum of the angles of a triangle = 180°
⇒ m∠A + m∠B + m∠C = 180°
⇒ 80° + 55° + m∠C = 180°
⇒ m∠C = 180° – 80° – 55°
⇒ m∠C = 45°
So, option C is not true.
Option D: m∠C = 80°
Already proved in option C that m∠C = 45°.
So, option D is not true.
Hence option B is the true statement that AB = 10.6 cm.
Answer: The answer is
Step-by-step explanation: Given that the area of the whole circle is represented by the expression
We are to find the area of the outer ring of the circle, i.e., to find the circumference of the circle.
Now, if 'r' represents the radius of the circle, then we have
Thus, the area of the outer ring is