You will need a calculator for this puzzle. Place the digits 1 through 9 in increasing order in the boxes, with no other symbols or exponents, so that each equation is true. Some equations involve negative numbers or fractions.

A. × ÷ ( + – ) = 1

B. ÷ × ( – ) + = 1

C. – ( × ÷ + ) = 2

D. + × ( – ( ÷ ) ) = 3

E. ÷ ( – ) × ( + ) = 3

F. + ( × – ) ÷ = 8

G. ÷ ( + – ) × = 9

H. × ( ÷ – ) + = 9

I. ( – ( ( + ) × ) ) ÷ = 13

J. + ( ( – ) × ÷ ) = 15

K. ( – + ( × ) ) ÷ = 15

L. ( – ) × ÷ + = 15

M. × ( + – ) ÷ = 16

N. ( – + ) ÷ ( × ) = 18

O. × ÷ – ( + ) = 18

P. ( + ( × ) ) ÷ ( – ) = 20

The solutions are here.