mgmat

[nafiul9090]

If x and y are nonnegative integers and x + y = 25, what is x?
(1) 20x + lOy < 300
(2) 20x + lOy> 280




statement 1
20x+10y<300
=2x+Y<30
=2x+y<25+5
=2x+y<x+y+5
=x<5
insufficient

statement 2
20x+10y>280
=2x+Y>28
=2x+y>25+3
=2x+y>x+y+3
=x>3
insufficient


together we get 3<x<5.so x must be 4

so answer is c

is my approach ok?

[vineeshp]

Looks fine to me.

Is there an issue with the answer?

[force5]

yes looks good nafiul9090. Answer has to be C

[Geva@EconomistGMAT]

If x and y are nonnegative integers and x + y = 25, what is x?
(1) 20x + lOy < 300
(2) 20x + lOy> 280




statement 1
20x+10y<300
=2x+Y<30
=2x+y<25+5
=2x+y<x+y+5
=x<5
insufficient

statement 2
20x+10y>280
=2x+Y>28
=2x+y>25+3
=2x+y>x+y+3
=x>3
insufficient


together we get 3<x<5.so x must be 4

so answer is c

is my approach ok?

It's good. Would just like to point out that you can also isolate (x+y) on the left side of the inequality and substitute that for 25, instead of isolating 25 on the right and substituting that for x+y.
For example:

Stat. (1)
20x+10y<300
=2x+Y<30
=x+x+y<30
=x+25<30
=x<5