We have a question: Percius has a collection of marbles. 40% of them are clear. 20% are black, and the remainder are all the other colors. A friend of his asks if he can take five marbles. On average, how many marbles of other colors will his friend end up getting?
And an answer: 2
So how you got the answer?
40% of the marbles are of other colors because 100 - 20 - 40 = 40. The friend will on average get 2 other colored marbles because 5 x .4 = 2.

We have a question: Roberto is out for a hike. He travels uphill at 2 MPH and downhill at 3MPH. The trail is 5 miles long. 60% is uphill and the rest is downhill. How long does it take him to complete it in minutes?
And an answer: 130
So how you got the answer?
There is 3 miles uphill because 5 x .6 = 3. This takes him 1.5 hours because 3 / 2 = 1.5. This takes him 90 minutes because 1.5 x 60 = 90. 40% of the trail is downhill because 100 - 60 = 40. There are 2 miles of downhill because 5 x .4 = 2. This takes him 2 / 3 of an hour because 2 / 3 = (2 / 3). This takes him 40 minutes because 60 x (2 / 3) = 40. It takes him 130 minutes in total because 90 + 40 = 130.

We have a question: Faith went to a baking shop and bought flour that cost $5 and a cake stand that costs $28. She then gave the cashier two $20 bills and $3 in loose coins. How much change will she receive?
And an answer: 10
So how you got the answer?
Faith must pay $28 + $5 = $33 for the flour and cake stand. Her two $20 bills amount to $20 x 2 = $40. So, she gave the cashier a total of $40 + $3 = $43. Hence, her change is $43 - $33 = $10.