Question

Incidence rate: Women 125 per 100,000 Men 1.2 per 100,000
This statistic says that for every 100,000 women in the U.S., 125 developed breast cancer. For every 100,000 men, fewer than two developed breast cancer.
From these numbers, we can see that breast cancer is about 100 times more common in women than in men (125 ÷ 1.2 = 104, or about 100).
Breast cancer in women by age
Overall, the average age at diagnosis of breast cancer for women is 61 in the U.S. (61 for white women and 57 for African American women).6 although younger women can be diagnosed with breast cancer, it is more common in women ages 50 and older.6-7
Women ages 20-49 Women ages 50 and older
Incidence rate 43 per 100,000 340 per 100,000

So, breast cancer is about eight times more common in women ages 50 and older than in women ages 20 to 49
(340 ÷ 43 = 8).
How can a change the problem into a algebra concept?