1998 Gauss Contest - Grade 7
Solutions
16. Each of the digits 3, 5, 6, 7, and 8 is placed one to a box in
the diagram. If the two digit number is subtracted from the
three digit number, what is the smallest difference?
(A) 269
(B) 278
(C) 484
(D) 271
(E) 261
Solution
The smallest difference will be produced when the three digit number is as small as possible, that is
356, and the two digit number is as large as possible, that is 87.
=
The smallest difference is 356 87 269
–
.
ANSWER: (A)
17. Claire takes a square piece of paper and folds it in half four times without unfolding, making an
isosceles right triangle each time. After unfolding the paper to form a square again, the creases on the
paper would look like
(A)
(B)
(C)
(D)
(E)
Solution
Fold 1
Fold 2
Fold 3
Fold 4
ANSWER: (C)
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