776 BC: First Olympiad in Greece.
4 BC: Birth of Jesus Christ.
570: Birth of Prophet Mohammed.
622: Beginning of Hijra Era.
1215: Signing of Magna Carta.
1492: Columbus discovered America.
1688: Glorious Revolution in England.
1776: American War of Independence.
1789: French Revolution.
1815: Battle of Waterloo.
1848: Publication of Communist Manifesto.
1918: First World War ended.
1948: Myanmar and Sri Lanka achieved independence.
1957: First artificial satellite was launched by Russia.
1963: Nuclear Test Ban Treaty.
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Reforms and Events During British Period Cabinet Mission – Wavell.
Communal Award – Wellington.
Doctrine of Lapse – Dalhousie.
Dyarchy – Chelmsford.
First Census – Ripon.
INA Trial – Wavell.
Jallianwala Bagh Tragedy – Chelmsford.
Permanent Settlement – Cornwallis.
Quit India – Linlithgow.
Sepoy Mutiny – Canning.
Subsidiary Alliance – Wellesley.
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N = the number of terms .
S = the sum of the numbers in the set.
Average = S/N .
For example.
The marks of a student in five subjects are 96, 94, 92, 87, and 81, then what is the average score of the student?.
N = 5.
S = 96 + 94 + 92 + 87 + 81 = 450.
A = 450/5 = 90.
Another type questions .
1). There are 36 boys and 44 girls in a class. The average score of boys is 40 and girls are 35. Then what will be the average mark? .
Total mark of 36 boys = 36 x 40 = 1440.
Total mark of 44 girls = 35 x 44 = 1540.
Total mark of 80 Students = 1440 + 1540 = 2980 .
Average mark of the class = (2980 / 80).
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