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Read the given statements carefully and ...

Read the given statements carefully and state 'T' for true and 'F' for false.
(i) If the ratio of three numbers is 3 : 4 : 5 and sum of their squares is 1250, then the sum of numbers is 60.
(ii) Decrease % = `(("Decreased value")/("New value") xx 100)%`
(iii) If an article is sold for Rs p after giving a discount of q %, then its marked price is Rs `(100p)/(100-q)`
(iv) If 44% of a number is 275, then 64 % of the same number is 400.

A

`{:(i,ii,iii,iv),(F,F,T,T):}`

B

`{:(i,ii,iii,iv),(T,F,T,T):}`

C

`{:(i,ii,iii,iv),(T,F,F,T):}`

D

`{:(i,ii,iii,iv),(F,T,F,T):}`

Text Solution

AI Generated Solution

The correct Answer is:
Let's solve the statements step by step. ### Statement (i) **Statement:** If the ratio of three numbers is 3 : 4 : 5 and the sum of their squares is 1250, then the sum of the numbers is 60. **Solution:** 1. Let the three numbers be \(3x\), \(4x\), and \(5x\). 2. The sum of their squares is: \[ (3x)^2 + (4x)^2 + (5x)^2 = 9x^2 + 16x^2 + 25x^2 = 50x^2 \] 3. Set this equal to 1250: \[ 50x^2 = 1250 \] 4. Divide both sides by 50: \[ x^2 = \frac{1250}{50} = 25 \] 5. Take the square root of both sides: \[ x = 5 \] 6. Now, calculate the three numbers: - \(3x = 3 \times 5 = 15\) - \(4x = 4 \times 5 = 20\) - \(5x = 5 \times 5 = 25\) 7. The sum of the numbers is: \[ 15 + 20 + 25 = 60 \] **Conclusion:** The statement is **True (T)**. ### Statement (ii) **Statement:** Decrease % = \(\frac{\text{Decreased value}}{\text{New value}} \times 100\)% **Solution:** 1. The formula for decrease percentage is actually: \[ \text{Decrease %} = \frac{\text{Decreased value}}{\text{Original value}} \times 100 \] 2. This means the statement is incorrect because it uses "New value" instead of "Original value". **Conclusion:** The statement is **False (F)**. ### Statement (iii) **Statement:** If an article is sold for Rs \(p\) after giving a discount of \(q\%\), then its marked price is Rs \(\frac{100p}{100-q}\). **Solution:** 1. Let the marked price be \(MP\). 2. The selling price \(SP\) after discount is given by: \[ SP = MP - \text{Discount} \] 3. The discount can be expressed as: \[ \text{Discount} = \frac{q}{100} \times MP \] 4. Therefore, we can write: \[ p = MP - \frac{q}{100} \times MP \] 5. Rearranging gives: \[ p = MP \left(1 - \frac{q}{100}\right) = MP \left(\frac{100 - q}{100}\right) \] 6. Solving for \(MP\): \[ MP = \frac{100p}{100 - q} \] **Conclusion:** The statement is **True (T)**. ### Statement (iv) **Statement:** If 44% of a number is 275, then 64% of the same number is 400. **Solution:** 1. Let the number be \(X\). 2. According to the statement: \[ 0.44X = 275 \] 3. Solving for \(X\): \[ X = \frac{275}{0.44} = 625 \] 4. Now, calculate 64% of \(X\): \[ 0.64 \times 625 = 400 \] **Conclusion:** The statement is **True (T)**. ### Final Answers - (i) T - (ii) F - (iii) T - (iv) T The final answer is **TFTT**.
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