Minus-Minus = Difference ①

Negative+negative+difference = 178 ②

Difference = 49 ③

We can know from ① that the minuend = minus+difference ④.

④ Substitute ② minus+difference+minus+difference = 178.

That is 2* (minus+difference) = 178.

Subtraction+Difference = 89 ⑤

③+⑤ 2* Difference = 49+89, Difference = 69, Subtraction +69 = 89 is substituted into ⑤, so Subtraction = 20.

So the minuend = 20+69 = 89

Answer: The minuend is 89, the minuend is 20 and the difference is 69.

Subtraction is the number subtracted from the minuend in the subtraction formula. In subtraction, for example, a-b=c, reading A minus B equals C, A is called minuend, and B is called minuend.

Subtraction is one of the basic operations in mathematics. Two numbers a and b are known. If there is a number c that satisfies b+c=a, then c is called the difference between a and b (and the difference is unique). The operation of finding the difference between two numbers is called subtraction, which is recorded as a-b=c, and pronounced as A minus B equals C, A is called the minuend, and B is called the minus sign. In the operation of finding another addend, in the arithmetic that can only use positive numbers, the minuend cannot be less than the minuend. Especially, for any number a, there are always a-a=0, a-0=a, and 0-0=0. After introducing negative numbers and negative signs, subtraction can be unified with addition, that is, a-b=a+(-b).

Subtraction-subtraction = difference;

Subtraction-difference = subtraction;

Subtraction+difference = minuend