(a) \(16:24::20:30\)
\(⇒\frac{ 16}{24} =\frac{ 20}{30}\)
\(⇒ \frac{2}{3} =\frac{ 2}{3}\)
Hence, it is True.
(b) \(21:6::35:10\)
\(⇒ \frac{21}{6} = \frac{35}{10}\)
\(⇒\frac{ 7}{2} = \frac{7}{2}\)
Hence, it is True.
(c) \( 12:18::28:12\)
\(⇒ \frac{12}{18} =\frac{ 28}{12}\)
\(⇒\frac{ 2}{3} ≠ \frac{7}{3}\)
Hence, it is False.
(d) \(8:9::24:27\)
\(⇒ \frac{8}{9} = \frac{24}{7}\)
\(⇒\frac{ 8}{9} =\frac{ 8}{9}\)
Hence, it is True.
(e) \(5.2:3.9::3:4\)
\(⇒\frac{ 5.2}{3.9} =\frac{ 3}{4}\)
\(⇒ \frac{4}{3} ≠ \frac{3}{4}\)
Hence, it is False.
(f) \(0.9:0.36::10:4\)
\(⇒\frac{ 0.9}{0.36} = \frac{10}{4}\)
\(⇒ \frac{5}{2}=\frac{5}{2}\)
Hence, it is True.
Determine if the following ratios form a proportion. Also, write the middle terms and extreme terms where the ratios form a proportion.
(a) 25 cm : 1 m and Rs 40 : Rs 160
(b)39 litres : 65 litres and 6 bottles : 10 bottles
(c) 2 kg : 80 kg and 25 g : 625 g
(d) 200 mL : 2.5 litre and Rs 4 : Rs 50
Complete the drawing shown in Fig. 9.14 to indicate where the free ends of the two wires should be joined to make the bulb glow