Question : In $\triangle$ABC and $\triangle$PQR, $\angle$B = $\angle$Q, $\angle$C = $\angle$R. M is the midpoint of side QR. If AB : PQ = 7 : 4, then $\frac{\text{area($\triangle$ ABC)}}{\text{area($\triangle$ PMR)}}$ is:
Option 1: $\frac{35}{8}$
Option 2: $\frac{49}{16}$
Option 3: $\frac{49}{8}$
Option 4: $\frac{35}{16}$
Correct Answer: $\frac{49}{8}$
Solution : In $\triangle ABC$ and $\triangle PQR$, $\angle B = \angle Q$ $\angle C = \angle R$ ⇒ $\angle A = \angle P$ ⇒ $\triangle ABC ~ \triangle PQR$ In $\triangle PQR$, Since PM is the median, it divides the triangle into two parts of equal areas. Area ($\triangle PMR) = \frac{1}{2} × \text {area} \;(\triangle PQR)$ -----------(i) Since the ratio of areas of two similar triangles is equal to the square of the ratio of their corresponding sides. $\frac{\text{area $(\triangle ABC$)}}{\text{area ($\triangle PMR)$}}$ = $\frac{\text{2×area $(\triangle ABC)$}}{\text{area $(\triangle PQR)$}}$ = $2×(\frac{7}{4})^2$ = $2×\frac{49}{16}$ = $\frac{49}{8}$ Hence, the correct answer is $\frac{49}{8}$.
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Question : In a $\triangle \mathrm{PQR}$ and $\triangle\mathrm{ABC}$, $\angle$P = $\angle$A and AC = PR. Which of the following conditions is true for $\triangle$PQR and $\triangle$ABC to be congruent?
Option 1: AB = PQ by SSS
Option 2: AB = PQ by SAS
Option 3: BC = QR by ASS
Option 4: $\angle$Q = $\angle$B by AAA
Question : In a $\triangle P Q R, \angle P: \angle Q: \angle R=3: 4: 8$. The shortest side and the longest side of the triangle, respectively, are:
Option 1: PQ and PR
Option 2: QR and PR
Option 3: PQ and QR
Option 4: QR and PQ
Question : Let $\triangle ABC \sim \triangle RPQ$ and $\frac{{area}(\triangle {ABC})}{{area}(\triangle {PQR})}=\frac{4}{9}$. If AB = 3 cm, BC = 4 cm and AC = 5 cm, then RP (in cm) is equal to:
Option 1: 6
Option 2: 5
Option 3: 4.5
Option 4: 12
Question : In $\triangle$PQR, $\angle$ PQR = $90^{\circ}$, PQ = 5 cm and QR = 12 cm. What is the radius (in cm) of the circumcircle of $\triangle$PQR?
Option 1: 6.5
Option 2: 7.5
Option 3: 13
Option 4: 15
Question : In $\triangle$ABC, $\angle$C = 90° and CD is perpendicular to AB at D. If $\frac{\text{AD}}{\text{BD}}=\sqrt{k}$, then $\frac{\text{AC}}{\text{BC}}$=?
Option 1: $\sqrt{k}$
Option 2: $\frac{1}{\sqrt{k}}$
Option 3: $\sqrt[4]{k}$
Option 4: $k$
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