If it takes one person 4 hours to paint a room and another person 12 hours to
paint the same room, working together they could paint the room even quicker, it
turns out they would paint the room in 3 hours together. This can be reasoned by
the following logic, if the first person paints the room in 4 hours, she paints 14 of
the room each hour. If the second person takes 12 hours to paint the room, he
paints 1 of the room each hour. So together, each hour they paint 1 + 1 of the 12 4 12
room. Using a common denominator of 12 gives: 3 + 1 = 4 = 1. This means 12 12 12 3
each hour, working together they complete 13 of the room. If 13 is completed each hour, it follows that it will take 3 hours to complete the entire room.
This pattern is used to solve teamwork problems. If the first person does a job in A, a second person does a job in B, and together they can do a job in T (total). We can use the team work equation.
Teamwork Equation: A1 + B1 = T1
Often these problems will involve fractions. Rather than thinking of the first frac-
tion as A1 , it may be better to think of it as the reciprocal of A’s time.
World View Note: When the Egyptians, who were the first to work with frac- tions, wrote fractions, they were all unit fractions (numerator of one). They only used these type of fractions for about 2000 years! Some believe that this cumber- some style of using fractions was used for so long out of tradition, others believe the Egyptians had a way of thinking about and working with fractions that has been completely lost in history.
90% of 100 = 0.9 x 100 = 90
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Answer: The visitor can see 90 ships.
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Answer:
Option b
Step-by-step explanation:
To solve this problem use the law of the sines.
We have 2 angles of the triangle and one of the sides.
The law of the sines is:
Then:
Answer:
$55
Step-by-step explanation:
its $150 - $40 = $110
$110 / 2 = $55
Answer:
A. 720 per hour
Step-by-step explanation:
1200+ <em>720</em> + 720 + <u>360</u> =3000
<em>hr 1↑</em>+ hr 2↑ + <u>↑30 min</u>
