Answer:
11. Not enough information
12. You can say DB = DC by SAA congruence rule and CPCTC (Corresponding parts of congruent triangles are congruent)
Step-by-step explanation:
For 12, you can say ΔABD≅ΔACD because they have a side in common (AD) and they have 2 congruent angles. Thus, you can use the SAA congruence criterion. Then, you can use CPCTC (Corresponding parts of congruent triangles are congruent) to say that DB = DC.
Hope this helps :)
Answer:
B. 23x-10
Step-by-step explanation:
to be sure that 2 of them will be blue i have to select 7+2=9 balls
7+8=15 balls in the urn
P=9/15
to be sure that 4 of them will be yellow i have to select 8+4=12 balls
P=12/15
In order to estimate the mean, you need to choose a value to represent the number in each category of accidents. It is often convenient to use the middle value of the range.
.. (4*6 +10*10 +15*6 +20*9)/(6 +10 +6 +9) = 394/31 ≈ 12.7