Math q3 reviewer part 2

If the sum of the interior angles of a polygon is x, then what is x in a 18-sided polygon?

• 2,520

• 1,080

• 2,880

• 2,340

Answer explanation

the formula for finding the sum of interior angles is (n-2)180

(18-2)180

16(180)

2,880

What is the measure of each interior angle of a regular nonagon?

• 130 degrees

• 120 degrees

• 135 degrees

• 140 degrees

Answer explanation

para makuha ang isang measurement ng interior angle, use the formula in getting the sum of the interior angles which is (n-2)180

since the problem is asking for the interior angle of a nonagon

(9-2)180= 1260

then divide 1260 by 9 para makuha ang one measurement of interior angle.

1260 /9 = 140 degrees

When the vertices of a regular polygon are on the circumference of a circle, what can you say about their relationship?

• The circle circumscribed about the regular polygon.

• The circle is inscribed in the regular polygon.

• The regular polygon is on the circle.

• The circle is on the regular polygon.

The rectangular pavilion with dimensions 50 m and 30 m to be paved with square tiles of side 25 cm price of Php 120.00 per piece or rectangular tiles with sides of 30 cm and 20 cm in the price of Php. 110.00 per piece. Which will be the best buy?

• The used of rectangular tiles since the cost of the tiles are cheaper.

• The used of rectangular tiles since its perimeter is greater than the square tiles.

• The used of square tiles since its perimeter is smaller.

• The used of square tiles since its area is greater than the rectangular tiles.

Answer explanation

1. step 1: get the area of the pavilion, convert the unit to cm; 1m = 100 cm

5000 cm x 3000 cm = 15,000,000 cm²

step 2: after that get the area of the square tiles

25x25= 625 cm²

step 3: divide the area of square tiles to the area of the pavilion

15,000,000/625 = 24,000 pcs

step 4: then multiply it to the cost of one square tile which is 120 pesos

24,000 x 120 = 2,880,000 pesos

repeat process for the rectangular tiles

area= length x width

then compare the prices

The circumference of a circle is 43.96 cm. How long is the radius?

note: to get the circumference of a circle, use the formula c= 𝜋d (use 𝜋 = 3.14)

• 4

• 5

• 6

• 7

Answer explanation

The diameter of a circle is twice its radius

Paul wants to find out the dimension of a rectangular garden. The length of the garden is six more than the width while the area is 27cm². What is the length?

• 3

• 6

• 9

• 12

Answer explanation

step 1: find out what the shape of the garden is

step 2: use the formula for getting the area of a rectangle area= length(width)

step 3: and sinabi sa problem na the length of the garden is 6 more than its width

meaning, width=x and length= 6+x

giving you;

27 cm² = x (6+x)

step 4: using the choices, substitute each values to x and solve the equation until you get an area of 27

One interior angle of a regular decagon is (5x – 8)°. Find the value of x.

• 30.4

• 33.4

• 36.4

• 35.4

The city administrators of Science City of Munoz plan to pave the 30m by 18m path of the City Hall with 60cm by 40cm cement tiles. How much money is needed to buy the cement tiles if each piece costs Php100?

• Php225,000

• Php250,000

• Php300,000

• Php320,000