If a parallelogram with area $P$, a rectangle with area $R$ and a triangle with area $T$ are all constructed on the same base and all have the same altitude, then which of the following statements is false?
Aptitude
Area
Difficulty: Medium
Choose an option
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A$P = R$
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B$P + T = 2R$
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C$P = 2T$
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D$T = \frac{1}{2} R$
Answer
Correct Answer: $P + T = 2R$
Explanation
### Concept & Logic
Compare the fundamental area formulas for shapes constructed on a common base ($b$) with a common altitude ($h$).
$$P = b \times h$$
$$R = b \times h$$
$$T = \frac{1}{2} \times b \times h$$
### Step-by-Step Solution
1. **Establish relationships:**
From the formulas, it is clear that $P = R$.
Also, since $T = 0.5 \times (b \times h)$, it follows that $T = 0.5 \times P$ (or $P = 2T$) and $T = 0.5 \times R$.
2. **Evaluate Option (a):** $P = R$. This is **True**.
3. **Evaluate Option (c):** $P = 2T$. This is **True**.
4. **Evaluate Option (d):** $T = \frac{1}{2} R$. This is **True**.
5. **Evaluate Option (b):** $P + T = 2R$.
Substitute $P$ and $T$ in terms of $R$:
$R + 0.5R = 1.5R$.
The statement claims it equals $2R$. Since $1.5R \neq 2R$, this statement is **False**.
### Exam Strategy & Shortcut
Assign simple numerical values! Let base = 10 and height = 10.
Then $P = 100$, $R = 100$, and $T = 50$.
Check (b): $100 + 50 = 150$. Does $150 = 2(100)$? No. The false statement is instantly identified.
### Common Pitfall
Misreading the question and selecting a *true* statement as the answer instead of correctly identifying the *false* one.
### Final Answer
Therefore, the correct answer is **$P + T = 2R$**.