Solution

154695

Problem / game
Inner equality Back to problem
First name
AMRIT W CASSIM
School
Hymers College
Country
United Kingdom, UK
Age
14

1 Let us split the inequalities
2 a+b>5 A
3 c+d<-5 B
4 B*-1: -c-d>5 B'
5 A+B':a+b-c-d>10
6 a+b<10 C
7 c+d>-10 D
8 D*-1: -c-d<10 D'
9 C+D':a+b-c-d<20
10 Collating these results, we have
11 10<a+b-c-d<20
12