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# Perimeter & Circumference

Directions: Using the digits 1-6, at most one time each, fill in the boxes to create the largest and smallest combined perimeter/circumference for the rectangle and circle. ### Hint

Which box number change has the greatest effect on the combined perimeter/circumference? Why?
What part of your calculations will be the same every time?

How many permutations are there of the numbers 1-6 in four positions?
Which permutations matter for the largest sum? Why?
Which permutations matter for the smallest sum? Why?

### Answer

greatest: (53 · 6) + (2π · 4) = 343.13… units

least: (24 · 1) + (2π · 3) = 42.85… units

Source: Christin Smith

## Converting a Fraction to a Decimal

Directions: Using the digits 1 to 9, at most one time each, place a digit …

### 7 comments

1. The solution given is actually for area of the rectangle and circumference of the circle

• Where do you put the numbers? Like which boxes? Thanks.

• You can choose to use any of the digits 1-6 in each of the boxes so that the rectangle has side lengths and the circle has a radius. You can only use each digit once.

2. Greatest: Rectangle with sides 63 and 4 and circle with radius 5. Answer: 165.4

• This is a solution but the one given in the answers is greater.

3. Least: Rectangle with sides 13 and 4 and circle with radius 2. Answer: 46.56

• Similarly with this solution Eric – it works but is not the smallest possible area.