Subject :IMO Class : Class 1
Ans 1:
Class : Class 4
sorry, 159 because a+b=27 b-a=9. Therefore a=18 b=9. d-c=3 and a+b+c+d=36 ab=27 so 36-27=9 d is bigger than c so d=6 c=3
a=18
b=9
c=3
d=6
final question a*b+c-d
18*9= 162
162+3=165
165-d or 165-6=159
ANSWER=159
Ans 3:
Class : Class 10
I find this question too high for Class 1. Anyway, I'll answer this.
Given that a+b=27; b-a=9; a+b+c+d=36. Substituting a+b=27 in a+b+c+d=36, 27+c+d=36-27=9. c+d=9; d-c=3.
Adding a+b and b-a, a+b+b-a=27+9, 2b=36, b=18. Therefore a=27-18=9.
Adding c+d and d-c, c+d+d-c=9+3, 2d=12, d=6. Therefore c=6-3=3.
Now, a=9; b=18; c=3; d=6.
a*b+c-d = 9*18+3-6 = 162+3-6 = 165-6 = 159.
Answer: 159