NIOS Class 10th Maths English Medium Solve Assignment (TMA) 2021

 Mathematics (211)

Tutor Marked Assignment

20% of Theory Marks

1. Answer any one of the following questions

(a) By selling a shirt to a customer for Rs. 749 a shopkeeper earns a profit of 7%. Find the cost price of the shirt.

Ans- CP = ( SP × 100 ) /( 100 + percentage profit).

So, Cost Price of Shirt = (749×100)/(100+7) = 700

2. Answer anyone out of the following questions.

(a) In the below-given figure, O is the Centre of a circle, find the value of x.

Ans- Angle PBO = 40

So angle OBQ = 90- 40 = 50

Angle BOQ = 90

So angle X = 180 – angle AOB – angle QBO = 180 – 90-50 = 40 (answer)

3. Answer anyone out of the following questions.

(a) The radius of the two circles are 9cm and 12cm. Find the radius of a circle whose area is equal to the sum of the areas of these two circles.

Ans- 𝜋𝑅² = 𝜋𝐴² + 𝜋𝐵²

= (A² + B²) = 𝜋(9² + 12²) = 𝜋(81 + 144) = 𝜋225

𝜋𝑅² = 𝜋225

R² = 225

𝑅 = 15 𝑖𝑠 𝑡ℎ𝑒 (𝒂𝒏𝒔𝒘𝒆𝒓)

4. Answer any one of the following questions.

(a) In the below given figure. ‘O' is the midpoint of AB and CD, Prove that AC= BD and AC || BD.

Ans-

In triangle AOC and BOD

AOC=BOD(VOA)

AO-BO(given)

CO=DO(given)

•AAOC-=ABOD(SAS rule)

•AC=BD(cpct)

•AC|| BD(alternate angles will be equal)

Hence proved (answer)

5. Answer anyone out of the following questions.

(a) From an external point two tangents PA and PB are drawn to the circle with Centre O. to prove that OP is the perpendicular bisector of AB.

Ans-

Let OP intersects AB at point C.

In ∆ PAC and ∆ PBC,

PA = PB (Tangents from an external point are equal)

∠APC = ∠BPC (PA and PB are equally inclined to OP)

PC = PC (common)

→ ∆PAC ≅ ∆ PBC (SAS criterion)

→ AC = BC and ∠ACP = ∠BCP

But, ∠ACP + ∠BCP = 180°

∠ACP = ∠BCP 90°

OP ⊥ AB

6. Prepare any one project out of the following projects given below.

(a) Conduct a survey of at least 50 households from your locality/village, regarding population and family income.

(i) Present the data related to family members in tabular form mentioning frequencies

Ans-

(ii) Calculate the average family size. How many families are above the average family size?

Ans-

(iii) Draw the Bar graph for the top 10 earning families.

Ans-