Step 1:

Find the probability atleast 2 girls in 7 births.

Probability of female birth is $\"\\small$ .

The probability for k successes is $\"image\"$ .

Where n is number of samples(trails),

p is probability of success,

q is probability of failure.

Here the number of samples are 7.

Probability of success is $\"\\small$ .

Probability of failure is $\"\\small$ .

Now probability of atleast 2 girls in 7 births is

$\"\\small$

Probability of atleast 2 girls in 7 births is 0.9375.

Solution:

Probability of atleast 2 girls in 7 births is 0.9375.