Answer:
Here is the complete question:
The ratio of the number of dogs to the number of cats is 4:5. There are 270 animals on the rescue farm. for each of the following statements, explain whether statements is true or false and why:
a. The number of dogs is 4/5 the number of cats.
b. 4/5 of the pets at the farm are dogs.
c. There are exactly 30 more cats than dogs.
d. There are exactly 30 dogs at the farm.
e. 5/9 of the pets at the farm are cats.
a,c and e are true statements.
Explanation:
Let the number of dogs be "d' and number of cats be "c".
According to the question:
⇒
...equation (i)
Arranging the ratio:
⇒
![(4)/(5) = (d)/(c)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/m2yacbh2x54vn0czzyp90coyvliiisxn1j.png)
⇒
![4c=5d](https://img.qammunity.org/2021/formulas/mathematics/middle-school/u28a3w05fkxux9mwu3q4p0hxnsbqquci3m.png)
⇒
...equation (ii)
Plugging (ii) in equation (i).
⇒
![c+d=270](https://img.qammunity.org/2021/formulas/mathematics/middle-school/n85xh9ig7vu6xel90xaz0cs51wv9g66xno.png)
⇒
![(5)/(4) d+d=270](https://img.qammunity.org/2021/formulas/mathematics/middle-school/gd4nbxtkyt69v3pyn6vhufjxt4v9yx5zde.png)
⇒
![(5d+4d)/(4) =270](https://img.qammunity.org/2021/formulas/mathematics/middle-school/n5cb91m23falx1gke1ihcz722oyf98qoix.png)
⇒
![9d=270* 4](https://img.qammunity.org/2021/formulas/mathematics/middle-school/7knrtniyejxm0cuvt19m2pocv1q8y5llta.png)
⇒
![d=(270* 4)/(9)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/d1rh1hv410wmaa36i3tx0dh0s0ummfaq6g.png)
⇒
![d=120](https://img.qammunity.org/2021/formulas/mathematics/middle-school/xentfcsqhph41sjskwc7813ie8mmpoukt4.png)
Number of dogs "d" = 120
Number of cats "c" = (270-120) = 150
Lets check each statement:
a.
The number of dogs is 4/5 the number of cats.
⇒
![(4)/(5) * 150](https://img.qammunity.org/2021/formulas/mathematics/middle-school/qtqqwz2x6m1jqy5mcbwut4qz18tgjw7ifk.png)
⇒
![(4* 150)/(5)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/n9eh82j1zospuy31cb3tabmyqta0ro39z5.png)
⇒
![120](https://img.qammunity.org/2021/formulas/mathematics/high-school/lx9358vvcad1dfeqkjf42amqw2ku2pbup8.png)
Statement is true.
b.
4/5 of the pets at the farm are dogs.
⇒
![(4)/(5) * 270](https://img.qammunity.org/2021/formulas/mathematics/middle-school/rtvpysif0qbt8apxepdf5z2jl7ztz5ud8a.png)
⇒
![216](https://img.qammunity.org/2021/formulas/mathematics/middle-school/bh3td7itno76gpvzdz040at4uab91oewm8.png)
Number of dogs = 120
So the above statement is false.
c.
There are exactly 30 more cats than dogs.
⇒
![c-d =30](https://img.qammunity.org/2021/formulas/mathematics/middle-school/tfuabtgjv5qqj1k0skenc8rvdrgsaexqne.png)
⇒
![150-120=30](https://img.qammunity.org/2021/formulas/mathematics/middle-school/9m51nie340kkegdqlyw58ocu6wsk6uz9ve.png)
Statement is true.
d.
There are exactly 30 dogs at the farm.
False, as there are 120 dogs
e.
5/9 of the pets at the farm are cats.
⇒
![(5)/(9) * 270](https://img.qammunity.org/2021/formulas/mathematics/middle-school/juyfkbp9gbmvuzi86axz1ezc3w9es8q5n5.png)
⇒
![150](https://img.qammunity.org/2021/formulas/mathematics/middle-school/nupeesxbqr0sx88jruaso52664ny1xdnfy.png)
Statement is true.
So,
Statement a,c and e are true as we could observe in the explanation.