Assume the rate of malignant breast cancer tumors is 1%. that means out of 10,000 mammograms, 100 women will have cancer (10,000 x 0.01 = 100) and the remaining 9900 will have benign tumors or nothing in the mammogram. a study
of 10,000 mammograms finds that they correctly identify a cancerous tumor 85% of the time. a particular
woman gets a positive mammogram. what is her risk of having a cancerous tumor?

When I see this equation, I can properly make the answer come out to 7.8 percent. I do this, by taking the 80 women, and dividing 80 women by the 80 women plus the 950 women, so 80/80+950 (or 80/1030=.078). So I get 7.8%, which should be the right answer.

But when I try to do the same with percentages, it all gets sort of screwy. I take the 80 percent of women (.8) divided by that same 80 percent (.8) plus 9.5 percent of women without cancer who test postive for it (.095). So I get .8/.8+.095=89%.

the answer is b i think

the journeys of marquette, joliet and la salle a) new france expand.

all three of these explorers explored the midwest and the area around the great lakes, which they subsequently claimed for france.

this was a big portion of territory and expanded new france which before then only consisted of quebec province in northeastern canada