Question

1500 families with 2 children were selected randomly and the following data were recorded .
Number of girls in family 2 1 0
Number of families 475 814 211

Answer 1

 power of 2, written in mathematics as √2 or 21⁄2, is the positive algebraic number that, when multiplied by itself, equals the number 2. Technically, it is called the principal square root of 2, to distinguish it from the negative number with the same property.

Geometrically the square root of 2 is the length of a diagonal across a square with sides of one unit of length; this follows the Pythagorean theorem. It was probably the first number known to be irrational.[citation needed]

As a good rational approximation for the square root of two, with a reasonably small denominator, the fraction 99/70 (≈ 1.4142857) is sometimes used.

The sequence A002193 in the OEIS consists of the digits in the decimal expansion of the square root of 2, here truncated to 65 decimal places:

Answer 2

Hope it helps you!!

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(i) Number of families with 2 girls = 475

Total number of families = 150

P(E) =(Number of favourable outcomes)/(Total number of event)

=475/1500

=19/60

(ii) Number of families with 1 girl = 814

P(E) = (Number of favourable outcomes)/(Total number of event)

=814/1500

=407/750

(iii) Number of families with no girl = 211

P(E) = (Number of favourable outcomes)/(Total number of event)

=211/1500