What is the number of sides of a polygon if four of its angles are 100 degrees each and the remaining angles are 160 degrees each?

To determine the number of sides of the polygon, we can use the properties of interior angles in polygons. First, we need to recall the formula for the sum of interior angles of a polygon with n sides, which is:

Sum of Interior Angles = (n – 2) × 180°

In this case, we know that four angles are each 100 degrees and the remaining angles are each 160 degrees. Let’s denote the total number of sides of the polygon as n. This means that:

Let m be the number of remaining angles:

n = 4 + m

Now, we can express the sum of all interior angles in terms of the known angles:

Sum of Interior Angles = 4 × 100° + m × 160°

Setting this equal to the formula for the sum of interior angles, we have:

4 × 100 + m × 160 = (n – 2) × 180

Substituting m = n – 4 into the equation gives:

4 × 100 + (n – 4) × 160 = (n – 2) × 180

This simplifies to:

400 + 160n – 640 = 180n – 360

Combining like terms results in:

800 = 20n

Next, we can solve for n:

n = 800 / 20 = 40

Thus, the polygon has 40 sides.

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