Any number that you can completely write down on paper using digits ... and a fraction bar or decimal point if necessary ... is a rational number. If you add it to 0.5, then the sum is another rational number.

**Answer:**

10x10x10

**Step-by-step explanation:**

that's basically it in standard form if that's what you meant

**Answer:**

**Step-by-step explanation:**

perimeter of rectangle=a+b+c

=3x+3x+15

=6x+15

if perimeter of rectangle is 90,

perimeter=a+b+c

90=3x+3x+15

90-15=6x

75/6=x

12.5=x

12 is 91 percent of 13.1 because if you divide 12 by 13 you will see that it is 92 percent but if you divide 12 by 13.1 you will get 91