List of practice Questions

If the selling price of 75 articles is equal to the cost price of 90 articles, then find the gain percentage.

PQ and RS are common tangents to two circles intersecting at points A and B. A and B, when produced on both sides, meet the tangents PQ and RS at X and Y, respectively. If AB = 3 cm and XY = 5 cm, then PQ is:

In a circle of radius 13 cm, a chord is at a distance of 12 cm from the center of the circle. Find the length (in cm) of the chord.

Let $q$ be the maximum integral value of $p$ in $[0,10]$ for which the roots of the equation $x^2-p x+\frac{5}{4} p=0$ are rational Then the area of the region $\left\{(x, y): 0 \leq y \leq(x-q)^2, 0 \leq x \leq q\right\}$ is

When 3.0g of carbon is burnt in 8.00g oxygen, 11.00g of carbon dioxide is produced. What mass of carbon dioxide will be formed when 3.00g of carbon is burnt in 50.0g of oxygen? Which law of chemical combination will govern your answer?

Match the organisms in Column A with their action in Column B.

A		B
(i)	Bacteria	(a)	Fixing nitrogen
(ii)	Rhizobium	(b)	Setting of curd
(iii)	Lactobacillus	(c)	Baking of bread
(iv)	Yeast	(d)	Causing malaria
(v)	A protozoan	(e)	Causing cholera
(vi)	A virus	(f)	Causing AIDS
		(g)	Producing antibodies

If wheat is sown in the kharif season, what would happen? Discuss.

Do you think there are also parents like Mrs. Pumphrey?

Compute the indicated products $(i)\begin{bmatrix}a&b\\-b&a\end{bmatrix}\begin{bmatrix}a&-b\\b&a\end{bmatrix}$$(ii)\begin{bmatrix}1\\2\\3\end{bmatrix}\begin{bmatrix}2&3&4\end{bmatrix}$$(iii)\begin{bmatrix}1&-2\\2&3\end{bmatrix}\begin{bmatrix}1&2&3\\2&3&1\end{bmatrix}$$(iv)\begin{bmatrix}2&3&4\\ 3&4&5\\ 4&5&6\end{bmatrix}\begin{bmatrix}1&-3&5\\ 0&2&4\\ 3&0&5\end{bmatrix}$
$(v)\begin{bmatrix}2&1\\3&2\\-1&1\end{bmatrix}\begin{bmatrix}2&-3\\1&0\\3&1\end{bmatrix}$$(vi)\begin{bmatrix}3&-1&3\\-1&0&2\end{bmatrix}\begin{bmatrix}2&-3\\1&0\\3&1\end{bmatrix}$

Explain the following terms with one example each.
(a) Corrosion
(b) Rancidity

The resistance $ R = \frac{V}{I} $ where $ V = (200 \pm 5) \, \text{V} $ and $ I = (20 \pm 0.2) \, \text{A} $. The percentage error in the measurement of $ R $ is:

The value of $ ^{49}C_3 ^{48}C_3 ^{47}C_3 ^{46}C_3 ^{45}C_3 ^{45}C_4 $ is

Define the term solution. How many types of solutions are formed? Write briefly about each type with an example.

Evaluate the following products without multiplying directly:

(i) 103 × 107 (ii) 95 × 96 (iii) 104 × 96

Using the number line write the integer which is :
(a) 3 more than 5
(b) 5 more than –5
(c) 6 less than 2
(d) 3 less than –2

For the reaction,

{C O}_{(g)} + {C l}_{2 (g)} ⇌ {C O C l}_{2 (g)}

, then

K_{p} / K_{c}

is equal to:

List the things that cause suffering and pain.

List the steps taken by the captain
(i) to protect the ship when rough weather began.
(ii) to check the flooding of the water in the ship.

What is the physical state of water at—
(a) 25°C
(b) 0°C
(c) 100°C ?

Three reasons why the author’s grandmother was disturbed when he started going to the city school.

The following frequency distribution gives the monthly consumption of electricity of 68 consumers of a locality. Find the median, mean and mode of the data and compare them

Monthly consumption (in units)	Number of consumers
65 - 85	4
85 - 105	5
105 - 125	13
125 - 145	20
145 - 165	14
165 - 185	8
185 - 205	4

If ΔABC is right angled at C, then the value of tan A + tan B is

How many litres of water will have to be added to 1125 litres of the 45% solution of acid so that the resulting mixture will contain more than 25% but less than 30% acid content?

State two economically important uses of:

heterotrophic bacteria
archaebacteria

What is the primary function of the large intestine in the human digestive system?