40 Number Crunch Problems by Shalosh B. Ekhad

FORTY
NUMBER CRUNCH PROBLEMS

SHALOSH B. EKHAD,

In these problems, the integers 1,2,3,4,5,6,7,8,9 appear each exactly once, in such a way that the equations are correct, with the usual convention that multiplication and division are performed before addition and subtraction. Otherwise, as usual the evaluation is from left to right. For example a-b-c is (a-b)-c NOT a-(b-c).

This kind of problems appear in the Australian daily newspaper "The Australian".

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

Problem 9

Problem 10

Problem 11

Problem 12

Problem 13

Problem 14

Problem 15

Problem 16

Problem 17

Problem 18

Problem 19

Problem 20

Problem 21

Problem 22

Problem 23

Problem 24

Problem 25

Problem 26

Problem 27

Problem 28

Problem 29

Problem 30

Problem 31

Problem 32

Problem 33

Problem 34

Problem 35

Problem 36

Problem 37

Problem 38

Problem 39

Problem 40