Question

please help me in solving Q-11 and 12. it's urgent.​

Answer 1

Question 11 :

Given :

• Diagonal (d₁) = 10 m
• Diagonal (d₂) = 15 cm

To FinD :

Cost of levelling the field.

Solution :

Analysis :

Here the area of rhombus is used. For levelling the field we need to find the area of rhombus.

Required Formula :

Area of rhombus = 1/2 × d₁ × d₂

where,

• d₁ = First Diagonal
• d₂ = 2nd Diagonal

Explanation :

We know that if we are given the two diagonals of the rhombus and is asked to find the area then our required formula is,

Area of rhombus = 1/2 × d₁ × d₂

where,

• d₁ = 10 m
• d₂ = 15 m

Using the required formula and substituting the required values,

⇒ Area of rhombus = 1/2 × d₁ × d₂

⇒ Area of rhombus = 1/2 × 10 × 15

⇒ Area of rhombus = 1 × 5 × 15

⇒ Area of rhombus = 1 × 75

⇒ Area of rhombus = 75

∴ Area of rhombus = 75 m².

Now the cost :

We know that if we are given the area and cost per m² of levelling the rhombus and is asked to find the total cost then our required formula is,

Total cost = Area × Cost per m²

where,

• Area = 75 m²
• Cost per m² = ₹ 200

Using the required formula and substituting the required values,

⇒ Total cost = Area × Cost per m²

⇒ Total cost = 75 × 200

⇒ Total cost = 15000

∴ Total cost = ₹ 15,000.

Cost of levelling the field is ₹ 15,000.

____________________________________________

Question 12 :

Given :

A letter is chosen random from the word "PROBABILITY".

To FinD :

• Probability the letter is a vowel.
• Probability of getting letter B.

Solution :

Analysis :

First we have to find out the total possible outcomes and then the favourable outcomes. Then dividing them both we can get our answer.

Explanation :

• Probability the letter is a vowel :

Here,

• Total no of outcomes = P, R, O, B, A, B, I, L, I, T, Y
• Favourable outcomes = O, A, I, I

We know that if we are given the total no of outcomes and favourable outcomes then our required formula is,

Probability(vowel) = Favourable outcomes/Total outcomes

where,

• Favourable outcomes = 4
• Total outcomes = 11

Using the required formula and substituting the required values,

⇒ P(vowel) = Favourable outcomes/Total outcomes

⇒ P(vowel) = 4/11

∴ Probability(vowel) = 4/11.

• Probability of getting letter B :

Here,

• Total no of outcomes = P, R, O, B, A, B, I, L, I, T, Y
• Favourable outcomes = B, B

We know that if we are given the total no of outcomes and favourable outcomes then our required formula is,

Probability(getting B) = Favourable outcomes/Total outcomes

where,

• Favourable outcomes = 2
• Total outcomes = 11

Using the required formula and substituting the required values,

⇒ P(getting B) = Favourable outcomes/Total outcomes

⇒ P(getting B) = 2/11

∴ Probability(getting B) = 2/11.

Probability the letter is a vowel is 4/11.

Probability of getting B is 2/11.