Answer:
The dimensions of the smallest piece that can be used are: 10 by 20 and the area is 200 square inches
Step-by-step explanation:
We have that:

Let the dimension of the paper be x and y;
Such that:


So:

Substitute 128 for Area

Make x the subject

When 1 inch margin is at top and bottom
The length becomes:


When 2 inch margin is at both sides
The width becomes:


The New Area (A) is then calculated as:

Substitute
for x

Open Brackets

Collect Like Terms



To calculate the smallest possible value of y, we have to apply calculus.
Different A with respect to y

Set

This gives:

Collect Like Terms

Multiply through by 


Divide through by 2

Take square roots of both sides



Recall that:



Recall that the new dimensions are:


So:




To double-check;
Differentiate A'




The above value is:

This means that the calculated values are at minimum.
<em>Hence, the dimensions of the smallest piece that can be used are: 10 by 20 and the area is 200 square inches</em>
Answer:
1.2 liters
Step-by-step explanation:
7/7 of a liter is one liter. and you still are only at 7. you need to get to 9 you and 2 1/7 liters and that becomes 9/7 liters which = 1.2
One box of candy costs $1.50. A movie rental costs $2.
21.2264 is 21.2 rounded to the nearest tenths; the place after the decimal is there tenths place so in the hundreths place, the number 2 is less than 5 therefore rounding it to 2.
Answer:
Area of circle R = 75π un² or ≈235.5 un²
Step-by-step explanation:
The problem says that m∠TRS = 120º. The total number of degrees in a circle is 360º. 120º is a third of 360º. Therefore, we can prove that the shaded sector is a third of the circle.
The problem then says that the area of the shaded sector is 25π and we have to calculate the area of the entire circle. Since we already know that the shaded sector is a third of the circle, we can simply multiply 25π by 3 in order to calculate the area of t he entire circle.
25π × 3 = 75π.
Area of circle R = 75π un² or ≈235.5 un²