Hi there! A = 78
A + 44 = B
We can plug in the values of A and B into the equation. We then get an equation with only one variable (x), which we can solve.
1x + 76 + 44 = - 6x + 134
Collect terms.
1x + 120 = - 6x + 134
Add 6x to both sides.
7x + 120 = 134
Subtract 120 from both sides
7x = 14
Divide both sides by 7
x = 14 / 7 = 2
A = 1x + 76
Now plug in the value of x we just found
A = 2 + 76 = 78
Answer:
By multiplying each ratio by the second number of the other ratio, you can determine if they are equivalent. Multiply both numbers in the first ratio by the second number of the second ratio. For example, if the ratios are 3:5 and 9:15, multiply 3 by 15 and 5 by 15 to get 45:75.
Since the dice are fair and the rolling are independent, each single outcome has probability 1/15. Every time we choose
We have 
and 
, because the dice are fair.
Now we use the assumption of independence to claim that
Now, we simply have to count in how many ways we can obtain every possible outcome for the sum. Consider the attached table: we can see that we can obtain:
- 2 in a unique way (1+1)
- 3 in two possible ways (1+2, 2+1)
- 4 in three possible ways
- 5 in three possible ways
- 6 in three possible ways
- 7 in two possible ways
- 8 in a unique way
This implies that the probabilities of the outcomes of 
are the number of possible ways divided by 15: we can obtain 2 and 8 with probability 1/15, 3 and 7 with probability 2/15, and 4, 5 and 6 with probabilities 3/15=1/5
Answer: C Hope it's helpful
