Topic: Exponents and Powers
Question: Suppose X=2100, Y=3100 and Z=4100. Exactly one of the following is true. Which is it?
Options: (a) X+Y=Z (b) X+Y<Z (c) X+Y>Z (d) XY=Z
Solution
1. Given values:
2. Comparing X+Y and Z:
3. Analysis: We can rewrite 4100 as:
Now compare:
Since 3>2, then 3100>2100. However, for large exponents:
2100+3100<3100+3100=2⋅3100
Comparing 3100 and 4100: As 3<4, then 3100 is significantly smaller than 4100. Even adding a smaller value like 2100 to 3100 will not make it reach 4100.
4. Verification:
ZX+Y=41002100+3100=(42)100+(43)100
Since both (21)100 and (43)100 are very small fractions (much less than 0.5):
Correct Option: (b) X+Y<Z