ACT Preparation / Unit 23 ACT 2212 worked example, 60 to 90 seconds
A Math Question From Start to Finish
The idea
A math question is worked in four steps. First, read to the question mark and mark what is asked: a value, an expression, a probability. Second, solve, choosing the fastest sound method, with the calculator where it helps. Third, look for your answer among the choices, and reread the question if it is missing. Fourth, check the answer against the question's units and sense.
In practice
Worked example: "A shirt costs $24 after a 20% discount. What was the original price?" Asked: the original price. Solve: 24 = 0.8 × p, so p = 30. The choices include $28.80, $30 and $19.20, and $30 is there. Check: 20% off $30 is $24.
Where people slip
A wrong choice can be the result of a predictable slip, such as adding 20% to $24 to get $28.80. A choice that matches a quick wrong method deserves a second look.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
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