If d represents the hundredths digit and e represents the thousandths digit in the decimal 0.4de, what is the value of this decimal rounded to the nearest tenth?
(1) d – e is equal to a positive perfect square.
(2) √d > e^2
we are allowed to use numbers < 10.
1. there are only 3 perfect squares in the available range. 1; 4; 9.
Pick 4. If d-e=4 then d might be 4 and e 0 or d might be 7 and e 3. If d=4 then our decimal remains 0.4; If d=7 our decimal becomes 0.5
2. since we know for sure that we are dealing with positive integers+0 we can safely say that if the square root of a number is greater than another number to the power of n, then the number under square root must be greater than the number to the power of n. This conveys us that d>e.
1+2) Both cases on statement 1) hold. (E)
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