189 + 555 + 211 + 45

= (189 + 211) + (555 + 45)

= 400 + 600

= 1000.

1555 + 455 + 1350 + 3650

= (1555 + 455) + (3650 + 1350)

= 2010 + 5000

= 7010

4555+5555×(23+17)

=4555+5555×40

 =4555+222200=226755

Last weekend, I did something good for my family that made me feel very happy. On Saturday morning, I saw that my mother was very busy with housework. She had to cook, clean, and do the laundry. I decided to help her by cleaning the floor and washing the dishes. At first, I felt a little tired, but when I saw my mother smiling, I knew it was worth it. Later, my father praised me and said I was becoming more responsible. My younger brother also joined me, and together we finished the work quickly. That day, I learned that even small actions can bring joy to the people we love. Helping my family not only made them happy but also made me proud of myself. I will try to do more good deeds like this in the future

12+52=1+52=62=3

(33+66)−2

=(1+1)-2

=2-2

=0

72+39=72+13

=216+26=21+26=236

− Trans: Tôi thức dậy vào buổi sáng

− get up (ph.v): thức dậy

− in + buổi trong ngày

Tổng 2 số đó là: 100

2 số là 2 số lẻ liên tiếp nên khoảng cách giữa chúng là 2

Số lớn là:

(100 + 2) : 2 = 51

Số bé là:

51 - 2 = 49

Gọi số cần tìm có dạng là ¯¯¯¯¯ab

Khi viết thêm số 3 vào bên trái số ban đầu thì số mới gấp 6 lần số cũ nên ta có:

¯¯¯¯¯¯¯¯3ab=6ׯ¯¯¯¯ab

=>300+¯¯¯¯¯ab=6ׯ¯¯¯¯ab

=>5ׯ¯¯¯¯ab=300

=>¯¯¯¯¯ab=60

Vậy: Số cần tìm là 60