Invertendo

Q.

There are 36 members in a student council in a school and the ratio of the number of boys to the number of girls is 3 : 1. How many more girls should be added to the council so that the ratio of number of boys to the number of girls may be 9 :5 ?

Q.

Question 59

An office opens at 9 AM and closes at 5:30 PM with a lunch break of 30 mim. What is the ratio of lunch break to the total period in the office?

Q.

If $A:B=5:6$ and $B:C=4:7$, Find $A:B:C$.

Q.

Question 49

Which ratio is larger 10 : 21 and 21 : 93?

Q.

Question 56

Of the 288 persons working in a company, 112 are men and the remaining are women. Find the ratio of the number of:
(a) men to that of women.
(b) men to the total number of persons.
(c) women to the total number of persons.

Q.

Question 77

In figure, what is the ratio of the areas of

a) shaded portion I to shaded portion II?

b) Shaded portion II to shaded portion III?

c) The shaded portion I and II taken together and shaded portion III?

Q.

Dylan drew 1 heart, 1 star, and 26 circles. What is the ratio of circles to hearts? What is the ratio of hearts to star? [2 MARKS]

Q.

The ratio of butter: flour: sugar in a recipe is $1:9:6$.

When using $8$ cups of sugar in this recipe, how many total cups of ingredients will be used?

Express your answer as a common fraction.

Q.

For four numbers a, b, c, d if a : b = c : d, then b : a = d : c. Which property of proportion is this?

1. Invertendo

2. Alternendo

3. Dividendo

4. Componendo

Q. If a : b :: c : d is correct then is also correct.

1. a : b : : d : c
2. b : a : : c : d
3. b : a : : d : c

Q.

Present age of father is $42\mathrm{years}$ and that of his son is $14\mathrm{years}$. Find the ratio of age of father to the age of son, when son was $12\mathrm{years}$ old.

Q. If 6 : 10 = 9 : 15, then 10 : 6 = ________.

1. 15 : 9
2. 9 : 15
3. 3 : 5
4. 1 : 2

Q.

Present age of father is $42\mathrm{years}$ and that of his son is $14\mathrm{years}$. Find the ratio of present age of father to the present age of son.

Q. If 2 : 4 = 3 : 6, then 4 : 2 = _________.

1. 2 : 4
2. 6 : 3
3. 1 : 2
4. None of the above

Q. If $a:b::c:d$ then $b:a::d:c$. This property is known as :

1. Invertendo property
2. Alternendo property
3. Componendo property
4. Dividendo property

Q. After applying invertendo to $3:7::2:9$ we get

1. $7:3::9:2$
2. $3:2::7:9$
3. $9:7::2:3$
4. $3:7::2:9$

Q. After applying invertendo to $1:2::8:9$ we get:

1. $1:8::2:9$
2. $2:1::9:8$
3. $8:9::1:2$
4. $1:9::8:2$

Q. After applying invertendo to $30:50::80:20$ we get $50:a::b:80$
Find the value of $a-b$

1. $10$
2. $20$
3. $30$
4. $40$

Q.

If a : b :: c : d then which of the following is correct?

1. a:b :: d:c

2. b:a :: c:d

3. b:a :: d:c

4. None of these

Q. If two ratios are equal then their inverse ratios are equal. This property is known as

1. Invertendo property
2. Dividendo property
3. Componendo property
4. Alternendo property

Q. (ma+nb):b::(mc+nd):d, prove a, b, c, d are in proportion by using componendo and dividendo

Q. Find the value of a and b respectively.
After applying invertendo to $3:5::8:9$ we get $5:a::b:8$ .

1. $5$ and $8$
2. $3$ and $9$
3. $9$ and $3$
4. $8$ and $5$

Q. Find the ratio in which the line joining the points $(6,3)$ and $(3,-5)$ is divide by the $x-$axis.

Q. After applying invertendo to $9:12::13:40$ we get

1. $9:13::12:40$
2. $40:12::13:9$
3. $9:12::13:40$
4. $12:9::40:13$

Q. Find the value of $a$ and $b$ respectively
After applying invertendo to $2:5::3:9$ we get $a:2::9:b$

1. $2$ and $9$
2. $9$ and $2$
3. $3$ and $5$
4. $5$ and $3$