Question
✓
Answer
We know that in a triangle if one side of it is produced, then
Exterior angle = sum of its interior opposite angles.
In fig., 125° = a + c .......(i)
and 140° = a + b ............(ii)
Adding, we get
a + c + a + b = 125° + 140°
⇒ a + a + b + c = 265°
But a + b + c = 180° ........(sum of angles of a triangle)
∴ a + 180° = 265°
⇒ a = 265° − 180° = 85°
But a + b = 140°
⇒ 85° + b = 140°
⇒ b = 140°− 85° = 55°
and a + c = 125°
⇒ 85° + c = 125°
⇒ c = 125° − 85° = 40°
Hence a = 85°, b = 55° and c = 40°
Exterior angle = sum of its interior opposite angles.
In fig., 125° = a + c .......(i)
and 140° = a + b ............(ii)
Adding, we get
a + c + a + b = 125° + 140°
⇒ a + a + b + c = 265°
But a + b + c = 180° ........(sum of angles of a triangle)
∴ a + 180° = 265°
⇒ a = 265° − 180° = 85°
But a + b = 140°
⇒ 85° + b = 140°
⇒ b = 140°− 85° = 55°
and a + c = 125°
⇒ 85° + c = 125°
⇒ c = 125° − 85° = 40°
Hence a = 85°, b = 55° and c = 40°
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(a) $\frac{72900}{\left(\frac{2}{3}\right)^n}$ $\quad$$\quad$(b) $\frac{2^n \times 27900}{3^n}$ $\quad$$\quad$(c) $\frac{72900}{3^n}$ $\quad$$\quad$ (d) $\frac{72900}{2^n \times 3^n}$
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Q.3. In how many years will the value of the computer be less than ₹ 200?
(a) 6 years $\quad$$\quad$(b) 7 years $\quad$$\quad$(c) 8 years $\quad$$\quad$(d) 10 years
Q.4. By how much will the value of the computer reduce in 4 years?
(a) ₹ 24300 $\quad$$\quad$(b) ₹ 1800 $\quad$$\quad$(c) ₹ 8100 $\quad$$\quad$(d) ₹ 72000
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