Add that number
Subtract that number
Times during the year
What year is this
100

10+10=

20

100

10-10=

0

100

What is the first month of the year

January

100

2024

Twenty-Twenty-Four 

200

21+21=

42

200

21-10=

11

200

What is the last month of the year

December

200

2025

Twenty-Twenty-Five

300

25+25=

50

300

24-15=

9

300

What is the third month of the year 

March

300

2000

Two-Thousand 

400

41+41=

82

400

36-16=

20

400

What is the sixth month of the year

June

400

1981

Nineteen-Eighty-One

1000

37+49=

86

1000

81-25=

56

1000

When is Chinese new year 

February

1000

2000 BC

Two-Thousand BC