Question 173
A whiteboard contains a calculation $1?2?3?4?5?6$, where each question mark is either a $+$ or a $\times$. The correct outcome of the calculation is written on the back of the board. Jaap copies the calculation but accidentally turns one of the plus signs into a times sign. The outcome is now $58$ more than the number on the back of the board. Jaap now changes a times sign back into a plus sign, but not on the place where he made the mistake before. Now the result differs $1$ from the previous result.
What number is on the back of the board?
What number is on the back of the board?