Problem of the Day #9 April 3, 2020

Problem of the Day #9 April 3, 2020

Grade 6: If 4 out of every 25 people have red hair, what percentage of people have red hair? 

Grade 7: Mrs. Johnson asks her students where they would like to go on vacation. Out of everyone in the class, 10 want to go to Hawaii, 14 want to go to Italy, 7 want to go to France, 3 want to go to New York and the rest are undecided. If 20% of the students want to go to Hawaii, how many students are in the class? 

Grade 8: Saturn in 1.4 x 10⁹ km from the Sun and Venus is 1.1 x 10⁸ km from the Sun. How much further from the Sun is Saturn than Venus? 

Algebra: Judy Jetson skateboarded from her house to her friend’s house at an average speed of 16km/h. Then she and her friend took a hovercraft to the mall. The hovercraft traveled at 80km/h. The entire trip took 4 hours and was a total distance of 224 km. How long was Judy riding her skateboard and how long was she and her friend in the hovercraft? 

Geometry: Cylinder A has a radius of 3 cm and a height of 4 cm. Cylinder B has a radius of 4 cm and a height of 3cm. What is the ratio of the volume of Cylinder A to Cylinder B? 

Algebra 2: A lightning hot shuttle plunged into a frozen lake. This caused the shuttle to cool off quickly. The relationship between the time since the shuttle hit the lake, in seconds and the temperature difference , D( t ) = 373 x ( 5/7)^t/2.4  The temperature difference is reduced by a factor of 5/7 every ____ seconds? 

Trigonometry: Find the midline, maximum and minimum of the following function:  y = 6 sin (2x -3) -5

Pre-Calculus:  Two popcorn kernels escaped from the pot. The first kernels displacement from the pot was ( 12,5 ) and the second kernels displacement was. (12, -16). How much further did the second kernel travel than the first? How far apart are the kernels? 

Answers: 

Grade 6: 16%

Grade 7: 16

Grade 8: 1.29 x 10⁹ km

Algebra: skateboard  1.5 hours,  hovercraft 2.5 hours

Geometry: 3/4

Algebra 2: 2.4

Trigonometry:  midline y = -5, maximum y = 1, minimum y = -11

Pre-Calculus: 7 ft further, 21 ft apart.