Answer:
a. 16
b. 80
c. Blood type AB
Step-by-step explanation:
Given:
O = 45%
A = 40%
B = 11%
AB = 4%
Total number of donors = 145
a. No. of donors that had type B blood = 
Type B blood donors ≈ 16
b. No. of blood donors without blood type O = 
Those without blood type O ≈ 80
c. Find the number of people that had type AB:
Type AB =
≈ 6. This is less than 10 donors.
Therefore, blood type AB had less than 10 donors.
Answer:
43,45
Step-by-step explanation:
43+45=88
Answer:

Step-by-step explanation:
⇒ 
⇒ 
⇒ 
The solution of this equation is -7.
3x - 7 = 4x
3x - 7 - 4x = 0
3x - 4x - 7 = 0
-x - 7 = 0
-x = 7
x = -7