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.
Answer:
120, 15
Step-by-step explanation:
Answer:
The surface area would be ten. Just remove the topmost cubes.
Step-by-step explanation:
Answer:
None of the expressions is equal to 0.7 x 0.41.
Step-by-step explanation:
Given that 0.7 x 0.41 is equal to 0.287, to determine which options are equal to said operation, the calculations set out for each of them must be performed:
A. 7,100 × 41100 = 291,810,000
B. 710 × 41100 = 29,181,000
C. 7100 × 4110 = 29,181,000
D. 710 × 4110 = 2,918,100
E. 70100 × 41100 = 2,918,100,000
Therefore, looking at all the results produced by the predisposed calculations, it is evident that none of the expressions is equal to 0.7 x 0.41.
Answer: 6 1/8
Step-by-step explanation:
1/8 x 2 = 1/8 x 2/1 = 2/8 = 1/4
1/4 x 3 = 1/4 x 3/1 = 3/4
3/8 x 4 = 3/8 x 4/1 = 12/8 = 1 4/8 = 1 1/2
1/2 x 3 = 1/2 x 3/1 = 3/2 = 1 1/2
5/8 x 1 = 5/8 x 1/1 = 5/8
3/4 x 2 = 3/4 x 2/1 = 6/4 = 1 2/4 = 1 1/2
Start with the big number first.
1 1/2 = 1 4/8
1 1/2 = 1 4/8
1 1/2 = 1 4/8
5/8 = 5/8
3/4 = 6/8
1/4 = 2/8
Add them all up.
1 4/8 + 1 4/8 = 2 8/8 = 3
3 + 1 4/8 = 4 4/8
4 4/8 + 5/8 = 4 9/8 = 5 1/8
5 1/8 + 6/8 = 5 7/8
5 7/8 + 2/8 = 5 9/8 = 6 1/8