Elijah builds model airplanes at a constant rate. He can build 5 model airplanes in 150 minutes, and 10 model airplanes in 300 minutes. How long would it take him to build 15 model airplanes.

450 minutes

Step-by-step explanation:

Since Elijah can build 5 model airplanes in 150 minutes. He can build 1 model airplane in 30 minutes. To find this you divide 150 by 5. The question asks for how many minutes it would take Elijah to build 15 model airplanes. Since 1 x 15 = 15 model airplanes, you use proportions and also multiple the time by 15, so 30 x 15 = 450 minutes.

1. 180°. the sum of the interior angles of a triangle is 180°, for the equilateral triangle that it has three equals side is 60°+60°+60°=180°.

2. 60°. each interior angle of a equilateral triangle is 60°

3. 120°. the measure of ∠m is 120°, the sum of the angles ∠m and ∠n is equal to 180°. so, in order to find the measure of ∠m, we have ∠m+∠n=180° > ∠m=180°-∠n > ∠m=180°-60°=120°.

4. 360°. the sum of the exterior angles of an equilateral triangle is ∠m+∠r+∠x=120°+120°+120°=360°. the exterior angles of any triangle always add 360°.