Question

The number of red blood cells per cubic millimetre of blood is approximately 5.5 million. If the average body contains 5 litres of blood, what is the total number of red cells in the body? Write the standard form. (1 litre = 1,00,000 mm³)

Answer 1

The average body contain 5 L of blood.

Also, the number of red blood cells per cubic millimetre of blood is approximately 5.5 million.

Blood contained by body = 5 L = 5 × 100000 mm³

Red blood cells = 5 × 100000 mm³

Blood = 5.5 × 1000000 × 5 × 100000

= 55 × 5 × 10^{5 + 5}

= 275 × 10¹⁰ 

= 2.75 × 10¹⁰ × 10² 

= 2.75 × 10¹²