Step-by-step explanation:
The area of a circle is given by :
A = πr²
r is the radius of the circle
(4) Diameter = 22 cm
Since, radius = diameter/2
r = 11 cm
Now, area of the circle,
(5) Diameter = 30 cm
Since, radius = diameter/2
r = 15 cm
Now, area of the circle,
(6) Diameter = 4cm
Since, radius = diameter/2
r = 2 cm
Now, area of the circle,
So, the area of circles 4,5 and 6 are 380.13², 706.85² and 12.56² respectively.
Probability of choosing pink balloon is .
Step-by-step explanation:
Given,
Number of green balloons = 5
Number of yellow balloons = 3
Number of red balloons = 4
Number of pink balloons = 8
Total number of balloons = 5+3+4+8 = 20
To find the probability of pink balloon.
Formula
Probability of an even = number of outcomes ÷ total number of outcomes
So,
Probability of choosing pink balloon = =
Answer: There are 48 students in the class.
Step-by-step explanation:
Let the number of students = S
Let the number of benches = B
<em>If 4 students sit on each bench, 3 benches are left vacant.</em>
S = 4(B - 3)
S = 4·B - 12 } Equation 1
<em>If 3 students sit on each bench, 3 students still standing.</em>
S = 3·B + 3 } Equation 2
We can match the two equations because they both indicate the same number of students.
4B - 12 = 3·B + 3
on solving this
4·B - 3·B = 3 + 12
B = 15 → number of benches
That is the number of benches, therefore substituting the value for B in equation 1
S = 4·B - 12 Equation 1
S = 4·15 -12
S = 60 - 12 = 48 → number of students
Answer: There are 48 students in the class.
<h3>Verification</h3>There are 48 students and 15 benches.
<em>If 4 students sit on each bench, 3 benches are left vacant.</em>
48students ÷ 4students/bench = 12 benches are occupied and left 3 vacant benches.
<em>If 3 students sit on each bench, 3 students still standing.</em>
<h3 />15benches * 3 students/bench = 45 students are sitting and 3 students remain standing.
<h3>Checked!!</h3>