Peter walks for 300m and his walking speed is 5 m/s. How many seconds are required
to finish the walk?

John needs 21 days to finish a project. Mary needs 42 days to finish the same project. If
John and Mary do the project together, how long do they need to finish it?

Ming’s grandmother’s age this year adds 14, multiples 2, minuses 56 and then divides
by 9. The result will be 16 years old. How old is Ming’s grandmother this year?
Lấy tuổi bà của Ming năm nay cộng 14, rồi nhân 2, trừ 56 và sau đó chia cho 9. Kết quả
thu được là 16 tuổi. Hỏi bà của Ming năm nay bao nhiêu tuổi?

A stationery store had a batch of ball pens. One half and 5 more pens were sold on the first
day. One half of the remaining part and 8 more pens were sold on the second day. Finally,
24 ball pens are left. How many ball pens did the stationery store have initially?

Find the value of 121 x 111

Find the value of 1 x2+ 2x 3 +3x 4 +...+17x 18+ 18x 19 +19x 20

Find the value of 1003x 1003 -997 x997

Find the value of 1/2 + 1 /4 + 1/8+ 1/16+1/32+ 1/64

Find the value of 2.01x 10 +2.01x 20 +2.01 x30 +2.01 x40