A4-digit number ends in 3. if you put the number 3 in the first position, the number will decrease by 738. find the original 4-digit number.

The original number is 4 1 5 3 OR 4 5 8 3

Step-by-step explanation:

* Lets find a way to solve this problem

- The end of the 4-digit number is 3

∴ The number is # # # 3

- The number decrease by 738 if the 3 becomes the first number

∴ The new number is 3 # # #

- Make it as a subtraction problem

∵ # # # 3 - 3 # # # = 0 7 3 8

- Lets subtract

∵ 3 - # = 8

∵ 8 > 3 we must borrow 1 from the number before 3

∴ 13 - 8 = 5

∴ # # # 3 - 3 # # 5 = 0 7 3 8

- Put the 5 in the first number, we can not pot it as a first number

 bwcause when we subtract it from 3 the answer will be 2 but we

 need answer zero

∴ Lets put it before the 3

∴ # # 5 3 - 3 # # 5 = 0 7 3 8

∵ we borrowed 1 from the 5 before

∴ 4 - # = 3

∴ # = 4 - 3 = 1

∴ # # 5 3 - 3 # 1 5 = 0 7 3 8

- Now we must use the 1 in the first number we can not put it as a

 number because it is smaller than 3, we must put it in the 2nd

 missing place

∴ # 1 5 3 - 3 # 1 5 = 0 7 3 8

∵ 1 - # = 7

∵ 1 < 7 so we must borrow 1 from the number before it

∴ 11 - # = 7

∴ # = 11 - 7 = 4

∴ # 1 5 3 - 3 4 1 5 = 0 7 3 8

- We must use the 4 in the first number and we have only one

 missing place (the first place)

∴ 4 1 5 3 - 3 4 1 5 = 0 7 3 8

∴ The original number is 4 1 5 3

* You can find another answer if you put the 5 in the 2nd place in the

 first number the answer will be 4 5 8 3 try to do it