pstew06 wrote:

E.

Two ways to solve:

1.) chunk it out mathematically:

a - min: 451 + 351 = 802

max: 449 + 449 = 948

answer set: 800, 900

INSUF

b - min: 451 + 351 = 802

max: 549 + 399 = 948

answer set: 800, 900

INSUF

a&b - min: 451 + 351 = 802

max: 499 + 399 = 898

answer set: 800, 900

INSUF

But this is way too long for the GMAT.

2.) Calculate the base:

min: 451 + 351 = 802 (or > 800)

max: 549 + 449 = 998 (or < 1000)

Answer set: 800, 900, 1000

Then look at options. You'll never take off more than 100, so you'll always be stuck with both 800 or 900 in the possible set.

please help me to understand the QUESTION first. Might than i will able to understand your ans.