Alternando

Q.

If three homogeneous quantities a, b and c are in continued proportion, such that $\frac{a}{b}=\frac{b}{c}or{b}^2=acorb=\pm \sqrt{ac}$, then b is said to be the mean proportional of a and c

1. False

2. True

Q.

Two numbers within the brackets denote the ranks of $10$ students of a class in two subjects $(1,10),(2,9),(3,8),(4,7),(5,6),(6,5),(7,4),(8,3),(9,2),(10,1)$, then rank correlation coefficient is

1. $0$

2. $-1$

3. $1$

4. $0.5$

Q.

If $\frac{8a-5b}{8c-5d}=\frac{8a+5b}{8c+5d}$, then $\frac{a}{b}=\frac{c}{d}$

1. True

2. False

Q.

After recording the height and weight, Ted wanted to know who is taller? Him or Ned. For that, he asked Ned’s height. He told that it was 135 cm and Ted’s height was 4.5 ft. Given 1 foot = 0.3 meters, what will be the value of $\frac{Ne{d}^{\prime }sheight}{Te{d}^{\prime }sheight}$?

1. 100

2. 30

3. 1
4. 0.01

Q.

If the cost of one notebook is Rs 40, then the cost of 19 similar notebooks is ___.

Q.

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

1. Invertendo

2. Alternendo

3. Dividendo

4. Componendo

Q.

If $f:R\to R$ satisfies $f(x+y)=f\left(x\right)+f\left(y\right)$, for all $x,y\in R$ and $f\left(1\right)=7$ , then ${\sum }_{r=1}^{n}f\left(r\right)$ is

1. $\frac{7n(n+1)}{2}$

2. $\frac{7n}{2}$
   

3. $\frac{7(n+1)}{2}$
   

4. 7n+(n+1)

Q. The given property $a:b::c:d$ then $a:c::b:d$ is known as:

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

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

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

Q.

If 0.75 : x :: 5 : 8, then x = _______

1. 1.5

2. 1.2

3. 1.8

4. 3

Q.

$\frac{3a-5z}{3b-5y}=\frac{3a+5z}{3b+5y}$. Then, $\frac{a}{b}=\frac{z}{y}$

1. True

2. False

Q.

If a : b = c : d, then according to alternendo property

1. a : c = b : d

2. a : d = b : c

3. b : a = d : c

4. a + b : b = c + d : d

Q. If (7a + 8b) (7c – 8d) = (7a – 8b) (7c + 8d);
Prove that a: b = c: d

Q.

If the cost of one notebook is Rs 40, then the cost of 19 similar notebooks is _________

___