mixture problems and d=rt problems

Joanna drives for 400km at an average speed of 80km/h. How long was her journey?

• Joanna's journey was 5hrs long
• Joanna's journey was 10hrs long
• Joanna's journey was 20hrs long
• Joanna's journey was 15hrs long

Tags

CCSS.6.RP.A.3B

Alan travels 100 km in 5hrs. Find his average speed in km/h

• 5km/hr
• 10km/hr
• 50km/hr
• 20km/hr

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

Reese rides her bike 10 miles in 5 hours.
Avery rides her bike 15 miles in 5 hours. Which girl rides her bike faster?

• Reese
• Avery 

Tags

CCSS.6.RP.A.3B

An aircraft carrier travels a distance of 1,000 kilometers in three days. What is its average rate of speed?

• a. 1,000 km/hr

• b. 3,000 km/hr

• c. 333.3 km/hr

• d. 13.9 km/hr

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

CCSS.6.NS.B.2

CCSS.6.RP.A.3

A chemist needs a 30% iron alloy. How many grams of a 70% iron alloy must be mixed with 16 grams of a 20% iron alloy to obtain the required

30% alloy?

• 28 grams

• 20 grams

• 12 grams

• 4 grams

Tags

CCSS.8.EE.C.7B

A history professor weights his grades as follows:

Tests 50%

Attendance 25%

Final exam 25%

If Susy earned an average of 91 on her tests, 80 on her attendance and 85 on her final exam, what will her final grade in the class be?

• 85.33

• 85

• 86.75

• 83.75

Tags

CCSS.6.EE.B.6

During a science experiment, Josephine created a 12% alcohol solution by mixing 8 fluid ounces of a 14% alcohol solution with a certain amount of a 4% alcohol solution. How many fluid ounces of the 12% alcohol solution did she create?

• 2 fl oz

• 4 fl oz

• 8 fl oz

• 10 fl oz