Question 24: Each letter represents a different digit from 0 to 9. If E=5, what number does SPEED stand for?

SPEED

SPEED

+SPEED

KILLS

Predict: I thought this would be about addition.

Clarify: I had nothing to clarify.

Find the big picture: What number does SPEED stand. for

Solve: Firstly I guessed that D would be 4, so then that would be 12, and S would be 2.

Then I worked out that if E=5, then 5+5+5+1 would be 16, so L would be 6.

Next I did the same thing with the next column, carried the one, and then went to the next.

Then I guessed that P was 3, so 3+3+3 is 9 plus 1 is 10, so I is 0 and then I carried the one.

Finally, I new that S had to be 2, so 2+2+2 is 6 plus 1 is 7, so K=7

So SPEED is 23554.

Summary: I used the guess, check and improve strategy.