Answer
a) y | p(y)
25 | 0.8
100 | 0.15
300 | 0.05
E(y) = ∑ y . p(y)
E(y) = 25 × 0.8 + 100 × 0.15 + 300 × 0.05
E(y) = 50
average class size equal to E(y) = 50
b) y | p(y)
25 | 
100 | 
300 | 
E(y) = ∑ y . p(y)
E(y) = 25 × 0.4 + 100 × 0.3 + 300 × 0.3
E(y) = 130
average class size equal to E(y) = 130
c) Average Student in the class in a school = 50
Average student at the school has student = 130
b is two fifths of c, so we make this a ratio with c = 1.
The ratio of b:c is 2/5 : 1
We also have 4a = 3c, rewrite this ratio so c is 1 by dividing both sides by 4,
so we get the ratio of a to c as 3/4 : 1
Now we get the a:b:c ratio of 3/4 : 2/5 : 1 now we can change the fractions to whole numbers, first by multiplying the 3 numbers by 4 to get get rid of the denominator of 4 in a:
3 : 8/5 : 4
Now multiply the 3 numbers by 5 to remove the denominator of 5 in b:
15 : 8 : 20
Now we can check using the equations:
b is 2/5 of c: 20 x 2/5 = 40/5 = 8 This is true.
4a = 3c: 4(15) = 3(20) = 60 = 60, this is also true.
The ratios is 15 : 8: 20
Answer:
Volume of composit figure= 4834.14 cm^3
Step-by-step explanation:
here's your solution
=> Radius of hemisphere = 9 cm
==> volume of hemisphere = 2/3πr^3
==> volume of hemisphere = 2/3*22/7* 9^3
==> volume = 1526.04 cm^3
=> Radius of cylinder = 9 cm
=> Height of cylinder = 13 cm
==> volume of cylinder = πr^2h
==> volume of cylinder = 22/7*9^2*13
==> volume of cylinder = 3,308.1 cm^3
Volume of composit figure = 1526.04 + 3308.1
= 4834.14 cm^3
hope it helps
Answer:
<em>25 mg. is lighter than 25 cg.</em>
<em />
Step-by-step explanation:
<em>Well,</em>
<em />
<em>The prefix "milli" means thousandth and the prefix "centi" means hundredth. So a milligram will be one-tenth of a centigram.</em>
<em />
<em>10 mg. = 1 cg.</em>
<em>25 mg. = 2.5 cg.</em>
<em />
<em>2.5 cg. < 25 cg.</em>
<em />
<em>25 mg. is lighter than 25 cg.</em>
