Question
Find the circumference and area of a circle with radius
10.5 cm. Take π = 22/7.Solution
Radius r = 10.5 cm = 21/2 cm Circumference = 2πr = 2 × (22/7) × (21/2) 2 cancels: = (22/7) × 21 = 22 × 3 = 66 cm Area = πr² = (22/7) × (21/2)² = (22/7) × (441/4) = (22 × 441) / 28 Simplify: 441 ÷ 7 = 63, so = (22 × 63) / 4 = 1386 / 4 = 346.5 cm² Answer: Circumference = 66 cm; Area = 346.5 cm².
17 32 99 ? 1965 11784
...77 ? 190 257 331 412
...Given below are three numbers series I, II and II where each series contains a wrong (odd one out) term. The wrong number in series I, II and III are '...
91   93   97   100   ?   113
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13 15 ? 63 143 293
...102     153      306      765       ?     8032.5
...17 ? 33 44 57 72
...3 5 7 25 85 481
...1 4 13 46 ? 976
...
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