Answer:
$30 in total.
Step-by-step explanation:
Since he owes 3 people 10 dollars each, you simply need to multiply:
10×3= $30 dollars in total.
D=event that chip selected is defective
d=event that chip selected is NOT defective
Four possible scenarios for the first two selections:
P(DDD)=15/100*14/99*13/98=13/4620
P(DdD)=15/100*85/99*14/98=17/924
P(dDD)=85/100*15/99*14/99=17/924
P(ddD)=85/100*84/99*15/98=17/154
Probability of third selection being defective is the sum of all cases,
P(XXD)=P(DDD)+P(DdD)+P(dDD)+P(ddD)
=3/20
7/12*6/14
7*6=42
12*14=168
=42/168
=0.25 =1/4
65 divided by 7 is approximently 9, and 25 divided by 7 is approximently 3, so 9 plus 3 is 12, so Gracie must wash 12 cars to earn enough money to save 25 and spend 65!
The equation of the tangent line can be found using slope formula and fact that slope = dy/dx.

where (x0,y0) is point A ---> (0,-1)
Then rearrange equation into slope-intercept form:

Finally sub in x=0 into dy/dx to get slope at the point (0,-1)