(1 point)

Responses

27 cats
27 cats

18 cats
18 cats

9 cats
9 cats

3 cats
3 cats
Question 2
Peter runs at a pace of 10 minutes per mile and starts a 5-mile run at 7:00 am. Alice, who runs at a pace of 5 minutes per mile, starts the same run at 7:15 am. At what time does Alice catch up with Peter?(1 point)
Responses

7:30 am
7:30 am

7:40 am
7:40 am

7:50 am
7:50 am

8:00 am
8:00 am
Question 3
A wooden block is in the shape of a cube. Each face of the cube is divided into four identical squares, and all of these squares are painted either red or green. If each face of the cube must have at least one square of each color, what is the greatest number of green squares that can be painted?(1 point)
Responses

12
12

18
18

20
20

24
24
Question 4
A new juice shop offers a special juice mix that consists of any two of the following juices: carrot juice, celery juice, apple juice, and pear juice. How many possible combinations can the shop make for this special juice mix? (Note: Assume two portions of the same juice do not constitute a mix).(1 point)
Responses

4
4

6
6

12
12

24

1 answer

Let's solve each question step by step:

Question 2:

  • Peter runs at a pace of 10 minutes per mile.
  • He starts running at 7:00 am.
  • Therefore, in 15 minutes (by 7:15 am), he has covered \( \frac{15}{10} = 1.5 \) miles.
  • Alice runs at a pace of 5 minutes per mile and starts at 7:15 am.

Let's denote the time from 7:15 am as \( t \). In \( t \) minutes:

  • Alice runs \( \frac{t}{5} \) miles.
  • Peter runs \( 1.5 + \frac{t}{10} \) miles.

To find when Alice catches up with Peter: \[ \frac{t}{5} = 1.5 + \frac{t}{10} \]

Multiplying the entire equation by 10 to eliminate the fractions: \[ 2t = 15 + t \] \[ 2t - t = 15 \] \[ t = 15 \]

Since Alice starts running at 7:15 am, she catches up with Peter at: \[ 7:15 am + 15 minutes = 7:30 am \]

Response for Question 2: 7:30 am


Question 3: The cube has 6 faces, each divided into 4 squares, so:

  • Total number of squares = \( 6 \times 4 = 24 \)

To satisfy the condition that each face of the cube must have at least one square of each color (red and green), we can consider the following strategy:

  • If we have 1 red square and 3 green squares on each face, we can maximize green squares while still meeting the requirement.

Calculating the total number of green squares: \[ 3\text{ green squares/face} \times 6\text{ faces} = 18\text{ green squares} \]

Thus, the greatest number of green squares that can be painted, while satisfying the color requirement, is: Response for Question 3: 18


Question 4: The available juices are:

  1. Carrot
  2. Celery
  3. Apple
  4. Pear

We need to find combinations of 2 juices out of these 4. This is a combinations problem, expressed as: \[ \text{Combination} = \binom{n}{r} = \frac{n!}{r!(n-r)!} \] where \( n \) is the total number of options, and \( r \) is the number of selections.

For this case: \[ n = 4 \quad \text{and} \quad r = 2 \] \[ \text{Combinations} = \binom{4}{2} = \frac{4!}{2!(4-2)!} = \frac{4 \times 3}{2 \times 1} = 6 \]

Response for Question 4: 6


Final Responses:

  • Question 2: 7:30 am
  • Question 3: 18
  • Question 4: 6