Lesson 1, 2, 3, 4

The age of Amy 7 years later is equal to the age of John 3 years later. Given that John is 25 years old now, how old is Amy now?

Tuổi của Amy 7 năm sau bằng tuổi của John 3 năm sau. Biết rằng hiện tại John 25 tuổi. Hỏi hiện tại Amy bao nhiêu tuổi?

Answer explanation

Method 1:

The age of John 3 years later is:

25 + 3 = 28 (years old)

Since the age of Amy 7 years later is equal to the age of John 3 years later, Amy's age 7 years later is 28 years old.

The age of Amy now is: 28 - 7 = 21 (years old).

The age of Tom 8 years ago is equal to the age of Jerry 3 years ago. Given Jerry is 20 years old now, how old is Tom now?

The age of Bruce 9 years ago is equal to the age of Peter 3 years later. Given Bruce is 18 years old now, how old is Peter now?

The age of Daisy 12 years later is equal to the age of David 3 years ago. Given Daisy is 18 years old now, how old is David 5 years later?

The age of Diana 4 years later is equal to the age of Mary 10 years later. Given Diana is 12 years old now, how old is Mary now?

If the day after tomorrow will be Wednesday, which day of the week will 17 days later be?

Nếu ngày kia là Thứ Tư. Hỏi 17 ngày sau là thứ mấy?

Answer explanation

Since the day after tomorrow will be Wednesday, today is Monday.

We have: 17: 7 get the remainder 3.

Therefore, 17 days later be is Thursday.

If the day after tomorrow will be Wednesday, which day of the week will 20 days later be?

Nếu ngày kia là Thứ Tư. Hỏi 20 ngày sau là thứ mấy?

Answer explanation

Since the day after tomorrow will be Wednesday, today is Monday.

We have: 20: 7 get the remainder 6.

Therefore, 20 days later be is Sunday.

Given that 17^th February 2020 is Monday, which day of the week will it be on 27^th April 2020?
Biết rằng ngày 17 tháng 2 năm 2020 là Thứ Hai. Hỏi ngày 27 tháng 4 năm 2020 là

thứ mấy?

Answer explanation

First, we need to find out how many days from 17th February 2020 to 27th April 2020.

• From 17/02/2020 to 17/03/2020, there are 29 days (note that 2020 is a leap year);

• From 17/03/2020 to 17/04/2020, there are 31 days;
  From 17/04/2020 to 27/04/2020, there are 10 days;

→ Therefore, from 17/02/2020 to 27/04/2020, there are: 29 + 31 + 10 = 70 (days)

Next, we have: 70: 7 has no remainder.

So, 27th April 2020 is Monday.

If the day after tomorrow is Friday, which day of the week the day before yesterday is?

Today is Friday 5^th April. Which day of the week is 1^st September in the same year?