Can someone help me with exercise 121?
1 answer:
You might be interested in
Well, 12 issues end up as 960 pages total
so... if in 960 pages, 384 are ads, what about 80 pages?
well
solve for "x"
so... if in 960 pages, 384 are ads, what about 80 pages?
well
solve for "x"
Answer:
There are 13 families had a parakeet only
Step-by-step explanation:
* Lets explain the problem
- There are 180 families
- 67 families had a dog
- 52 families had a cat
- 22 families had a dog and a cat
- 70 had neither a cat nor a dog, and in addition did not have a
parakeet
- 4 had a cat, a dog, and a parakeet (4 is a part of 22 and 22 is a part
of 67 and 520
* We will explain the Venn-diagram
- A rectangle represent the total of the families
- Three intersected circles:
C represented the cat
D represented the dog
P represented the parakeet
- The common part of the three circle had 4 families
- The common part between the circle of the cat and the circle of the
dog only had 22 - 4 = 18 families
- The common part between the circle of the dog and the circle of the
parakeet only had a families
- The common part between the circle of the cat and the circle of the
parakeet only had b families
- The non-intersected part of the circle of the dog had 67 - 22 - a =
45 - a families
had dogs only
- The non-intersected part of the circle of the cat had 52 - 22 - b =
30 - b families
had cats only
- The non-intersected part of the circle of the parakeet had c families
had parakeets only
- The part out side the circles and inside the triangle has 70 families
- Look to the attached graph for more under stand
∵ The total of the families is 180
∴ The sum of all steps above is 180
∴ 45 - a + 18 + 4 + 30 - b + b + c + a + 70 = 180 ⇒ simplify
- (-a) will cancel (a) and (-b) will cancel (b)
∴ (45 + 18 + 4 + 30 + 70) + (-a + a) + (-b + b) + c = 180
∴ 167 + c = 180 ⇒ subtract 167 from both sides
∴ c = 180 - 167 = 13 families
* There are 13 families had a parakeet only
