ALEKS Math common mistakes
ALEKS Math · Understand the traps and how to avoid them.
Entering a fraction answer as a rounded decimal (e.g., typing 0.333 instead of 1/3) when the problem asks for an exact value.
The candidate reaches for a calculator habit and treats the answer box as a decimal field, forgetting that exact rational answers are expected and accepted.
What to do instead
Before submitting, check whether the answer is a terminating decimal. If not, enter the fraction in lowest terms using the fraction-entry tool rather than a rounded value.
Solving an equation and reporting the value of an intermediate expression instead of the quantity the question actually asks for (e.g., finding x when the question asks for 2x + 3).
The candidate stops as soon as the variable is isolated, because that feels like the 'end' of the algebra, without re-reading the final sentence.
What to do instead
Underline the requested quantity in the prompt before starting, then after solving, substitute back into that expression and confirm the answer matches the asked-for form.
Dropping the negative sign or misplacing it when distributing a minus sign across a binomial, e.g., simplifying 5 - (2x - 7) as 5 - 2x - 7.
The eye groups the minus with the first term only; the distributive property over a subtraction is a common procedural gap under time pressure.
What to do instead
Rewrite every subtraction of a parenthetical as adding the negative before distributing: 5 + (-1)(2x - 7), then distribute to both terms explicitly.
Solving an inequality and keeping the inequality direction unchanged after multiplying or dividing both sides by a negative number.
The rule is learned alongside equation-solving and is easily overridden by the equation habit of preserving direction.
What to do instead
Whenever a negative multiplier or divisor is applied, draw an arrow and flip the symbol on that line before continuing; re-check by testing a sample value in the original inequality.
Treating a composition or function evaluation as multiplication, e.g., computing f(g(2)) as f(2) * g(2).
Notation like f(g(x)) visually resembles juxtaposition-multiplication, and the inner-to-outer evaluation order is not obvious.
What to do instead
Work strictly inside-out: evaluate the innermost function first, write its numeric result, then feed that number into the outer function as a fresh substitution.
Reporting a probability or ratio without reducing, or entering a percent where a fraction or decimal is required (or vice versa).
The candidate computes the correct count but ignores the required answer format shown in the input field or prompt.
What to do instead
Read the units/format cue in the prompt (fraction, decimal, or percent) and convert deliberately at the end; reduce fractions to lowest terms as a final step.
Using the limiting reactant's moles but forgetting to convert back to the requested unit (grams, liters of gas, or molarity) at the end of a stoichiometry problem.
The mole-ratio step is the cognitively heavy part, so the candidate treats reaching moles of product as the finish line.
What to do instead
Set up a single dimensional-analysis chain that begins with the given quantity and ends in the requested unit, so every conversion including molar mass is built into one line.
Balancing a chemical equation by changing subscripts in a formula instead of coefficients.
Changing a subscript 'makes the count work' visually and feels faster than iterating coefficients, but it changes the identity of the substance.
What to do instead
Adopt the rule that subscripts are immutable; balance only by placing coefficients, and finish by recounting each element on both sides.
Applying significant-figure or rounding rules inconsistently, e.g., rounding intermediate results or reporting more digits than the given data support.
Candidates round at each step because it simplifies arithmetic, and sig-fig rules are applied only sporadically.
What to do instead
Carry full precision through all intermediate calculations and round only the final answer, then count significant figures in the given values to set the final digit count.
Confusing molarity with moles or with mass when computing concentration, e.g., dividing grams by liters directly without converting to moles.
Molarity is defined as moles per liter, but the given mass is often the most salient number, so it gets used directly.
What to do instead
Write the target unit first (mol/L), then build the conversion from the given mass through molar mass to moles before dividing by volume in liters.