Question

Decode the addition or subtraction problem (Change asterisks to digits, to make the operations correct.) 6*5* − *8*4=2856

Answer 1

`\left\begin{array}{ccccc}&6&7&5&0\\-&3&8&9&4\\--&--&--&--&--\\=&2&8&5&6\end{array}\right`

Explanation:

`\left\begin{array}{ccccc}&6&*&5&*\\-&*&8&*&4\\--&--&--&--&--\\=&2&8&5&6\end{array}\right`

• 10-4=6

Therefore the last digit of 6*5* is 0.

• [(5-1)+10]-5=9
• 8+8+1=17
• 6-(1+2)=3

Therefore:

`\left\begin{array}{ccccc}&6&7&5&0\\-&3&8&9&4\\--&--&--&--&--\\=&2&8&5&6\end{array}\right`