Answer:
Each envelope is $1.42
Step-by-step explanation:
Let, the cost of postcards = x and the cost of envelopes = y, in dollars.
It is given that,
First customer paid $12 for 14 postcards and 5 envelopes.
This gives, 14x + 5y = 12.
Second customer paid $24.8 for 10 postcards and 15 envelopes.
This gives, 10x + 15y = 24.8
We get the system of equations,
14x + 5y = 12
10x + 15y = 24.8
We multiply 1st equation by 3. This gives us the equations,
42x + 15y = 36
10x + 15y = 24.8
Subtracting both equations, we get,
32x = 11.2
i.e. 
i.e. x = 0.35
Which gives,
10 × 0.35 + 15y = 24.8
i.e. 15y = 24.8 - 3.5
i.e. 15y = 21.3
i.e. 
i.e. y = 1.42
Hence, the cost of each postcard is $0.35 and each envelope is $1.42.
Originally Dan has X amount of base ball cards.
So the equation would be
(x+6)/2=29
multiply both sides by 2
x+6=58
subtract 6
x=52
Check your work: 52+6=58/2=29
Answer: AB ≅ CB
Step-by-step explanation:
In the given figure, we have ∆ABD ≅ ∆CBD
The CPCTC property of congruent triangles says that if two triangles are congruent then their corresponding parts ( angles and segments ) are congruent.
Since we have given that ∆ABD ≅ ∆CBD.
Therefore, the corresponding segments are congruent.
As segment AB is corresponding to segment CB. [First two letters]
Therefore, segment AB is congruent to segment CB.
Answer:
When 2 people work together the total time equals
Total Time = Time 1 * Time 2 / (Time 1 + Time 2)
Let's solve for Time 1 (which will be Tim's time.)
7 hours = Time 1 * 9 / (Time 1 + 9)
7 * Time 1 + 63 = Time 1 * 9
63 = 2 * Time 1
Time 1 = 30.5 Hours (Tim's Time)
Double Check
Total = 30.5 * 9 / (30.5 + 9)
Total = 274.5 / 39.5
Total = 7 Hours
Again, Tim's Time is 30.5 Hours
Step-by-step explanation:
