The right answer is Option A.
Step-by-step explanation:
Let,
x be the postcards
y be the large envelops
According to given statement;
14x+5y=12 Eqn 1
10x+15y=24.80 Eqn 2
Multiplying Eqn 1 by 3;

Subtracting Eqn 2 from Eqn 3;

Dividing both sides by 32

Putting x=0.35 in Eqn 1;

Dividing both sides by 5

Therefore, one large envelope costs $1.42
The right answer is Option A.
Keywords: linear equations, subtraction
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Answer:
8/14
Step-by-step explanation:
there are 5 odd numbers and 3 numbers are coloured red
14.1% of 278 is 39.2. So 39.2 megabytes have been downloaded.
Answer:
The perimeter of the garden, in meters, is 
Step-by-step explanation:
Diagonal of a square:
The diagonal of a square is found applying the Pythagorean Theorem.
The diagonal of the square is the hypothenuse, while we have two sides.
Diagonal of 12m:
This means that
, side s. So





Factoring 72:
Factoring 72 into prime factors, we have that:
72|2
36|2
18|2
9|3
3|3
1
So

So, in simplest radical form:

Perimeter of the garden:
The perimeter of a square with side of s units is given by:

In this question, since 

The perimeter of the garden, in meters, is 