Answer:
680 girls and 850 boys
Step-by-step explanation:
the ratio of girls is 4/9
then we can find the number of girls (G) in the group of 1530 students using proportions:
4 / 9 = G / 1530
solving for G by multiplying both sides of the proportion by 1530, we get:
G = 4 * 1530 / 9 = 680
So there were:
680 girls and 1530 - 680 = 850 boys
Answer:
it saves 2.5 minutes
Step-by-step explanation:
The expected value of a random variable is the sum of products of possibilities and the probability of each.
Here, you have a probability of 0.9 of saving 5 minutes, and a probability of 0.1 of adding 20 minutes.
__
The expected value of the shortcut is ...
0.9(-5) +0.1(20) = -4.5 +2.0 = -2.5
The shortcut is expected to save 2.5 minutes on average.
_____
<em>Additional comment</em>
The probability of 0.9 comes from the 9 of 10 trips that result in a time saving.
Answer:
2198 cm²
Step-by-step explanation:
Total surface area of a cylinder = 2πrh + 2πr²
Radius, r = diameter/2
= 20cm/2
= 10 cm
Height, h = 25 cm
Total surface area of a cylinder = 2πrh + 2πr²
= 2*3.14*10*25 + 2*3.14*10²
= 1,570 + 6.28*100
= 1,570 + 628
= 2198 cm²
Total surface area of a cylinder = 2,198 cm²
Answer:
Blue square
Step-by-step explanation:
looking like rhombus because right angle is 90 degrees and a square has 4 right angles
38.50/7 = $5.50 for each cases of water Heather bought.
