Adding 2 to half of one-third of one-fifth of an unknown number yields one-fifteenth of that number. Identify the number?
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Answer: C. 60
Explanation
Solving the algebraic equation systematically isolates the unknown variable to find the correct number. Substituting sixty into the original expression confirms that both sides yield exactly four units. Checking the calculations step by step verifies that sixty satisfies all conditions stated previously. Unknown number problems are translated into linear algebraic equations before attempting any solution steps. Fractions represent parts of a whole and are multiplied directly across their numerators and denominators. Isolating the variable requires combining like terms and applying basic arithmetic operations very carefully.
Algebraic word problems build essential critical thinking skills used extensively in higher mathematics courses. Similar multi-step equations appear frequently in financial modeling and engineering resource allocation scenarios. Mastering fractional manipulations helps students solve complex proportional reasoning tasks across various disciplines. Forty fails to satisfy the given condition because the resulting arithmetic does not balance correctly. Fifty produces an incorrect numerical value when substituted back into the original fraction equation. Seventy yields an unequal balance when evaluated against the target fraction on the right side.
- Subject
- Mathematics
- Category
- Mathematics
- Topic
- —
- Difficulty
- medium
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