A standard pair of six-sided dice is rolled. What is the probability of rolling a sum less than or equal to 7? Express your answer as a fraction or a decimal number rounded to four decimal places.

The perimeter of an equilateral triangle is 4 cm more than the perimeter of a square and the length of a side of the triangle is 8 cm more than the length of a side of the aware. find the length of a side of the equilateral triangle