Final answer:
Leukemia can cause low numbers of red blood cells, normal white blood cells, and platelets in the blood.
Step-by-step explanation:
A person with leukemia may have low numbers of red blood cells due to the cancerous cells crowding the bone marrow and preventing the production of healthy red blood cells. Leukemia can also lead to the destruction of red blood cells in the bloodstream. The white blood cells may be normal because leukemia originates in the bone marrow and affects the production of red blood cells more than white blood cells. Platelet numbers can be low because the cancerous cells can interfere with the production of platelets or cause them to be used up more quickly.
Learn more about Causes of low blood cell counts in leukemia