Question- Journal #3

Question:

Avertica post is to be supported by a wooden pole,secured on the ground at an angle of elevation of ,and reaching 3 m up the post from its base.If wood is sold by the foot ,how many feet of wood are needed to make the pole?

Answer:
                                                                                                

                                                                               

 

 L=3.46 * 3.05=12 ft                                                                 



The answer is 12 ft
But we can continue to find the next angle and side:

L^2=3^2+X^2 X^2=(3.46)^2-9 X=1.7 m X=5.18 ft and  :

Question- Journal #2

Question:

Bingo uses the numbers from 1 to 75.If the numbers are pulled and random,what is the probability that the first number is multiple of 5?is not a multiple of 5?

Answer:

75/5=15

There are 15 numbers which are multiple of 5,so there are 75-15=60 numbers which are not multiple of 5.


5,10,15,20,25,30,35,40,45,50,55,60,65,70,75

Probability of multiple 5 is  15/75=1/3

Probability of not multiple of 5 is  60/75=4/5

Question- Journal #1

Question:

The Neuman company is designing a new container for its marbles.The container must have a volume of 200 cm^3 .Sketch 3 possible containers and calculate each volume .Explain which container you would recommended.

Answer:

When a is length,b is width,c is height
V=200cm^3
V=a*b*c
S=2(b*c)+2(a*c)+(b*a)

1) When a=4,b=10,c=5
V=4*10*5=200  ,  S=2(10*5)+2(4*5)+(10*4)=100+40+40=180 cm^2

2) When a=5,b=10,c=4
V=5*10*4=200 , S=2(10*4)+2(5*4)+(10*5)=80+40+50=170 cm^2

3)When a=b=c=cuberoot 200=5.85
  S=2(5.85*5.85)+2(5.85*5.85)+(5.85*5.85)=68.4+68.4+34.22=171 cm^2

When we compare all 3 options ,we see  that #2 is more economical than the other 2 ways,because with the same volume, this container uses less material .