Home › Certifications › 7th Math: Ratios & Proportional Relationships › Computing Unit Rates with Complex Fractions
20 multiple-choice questions and 24 flashcards on Computing Unit Rates with Complex Fractions, about 13% of the 7th Math: Ratios & Proportional Relationships bank. Every one carries a written rationale.
Computing Unit Rates with Complex Fractions is one of 4 chapters in CoStudy's 7th Math: Ratios & Proportional Relationships bank, and it holds 20 of the bank's 150 multiple-choice questions — roughly 13% of the total. That proportion is not arbitrary: chapters follow the certifying body's published exam outline, and the number of questions in each is set by that domain's published weight, so the share of your practice time this chapter takes matches the share of the real exam it accounts for.
Studying by chapter is worth doing once you have a diagnostic score. A single overall percentage tells you whether you are close; it does not tell you which domain is dragging. Working a weak chapter in isolation, and re-testing it in isolation, is the fastest way to move a score that has stalled — and it is why the mock exams in CoStudy report by domain rather than as one number.
5 questions drawn from this chapter, with the full rationale shown — the controlling principle behind the right answer, and why each wrong option tempts and fails.
A bag of dog food weighing 30 lb costs $24. The unit price per pound is:
Answer: C — $0.80
C) $24/30 = $0.80/lb. A) Misdivided. B) Used 32 lb. D) Reversed: lb per dollar.
If 5/8 cup of paint covers 3 sq ft, the rate in square feet per cup is:
Answer: D — 4.8
D) 3 ÷ (5/8) = 3 × 8/5 = 24/5 = 4.8 sq ft/cup. A) Multiplied instead. B) Reversed: cups per sq ft. C) Wrong arithmetic.
5/6 yard of fabric costs $3. The unit price per yard is:
Answer: D — $3.60
3 ÷ (5/6) = 3 × (6/5) = 18/5 = $3.60/yard. (A), (C), (B) miscalculate.
If 1/2 cup of sugar is used per 1/4 cup of butter, the unit rate (cups of sugar per cup of butter) is:
Answer: B — 2
(1/2) ÷ (1/4) = (1/2)(4) = 2 cups of sugar per cup of butter. (A) multiplies; (C), (D) miscalculate.
Find the unit rate: 1/4 mile in 1/8 hour.
Answer: A — 2 mph
A) (1/4) ÷ (1/8) = (1/4)·8 = 2 mph. B) Reciprocated. C) Multiplied instead of dividing. D) Doubled the time, not divided.
3 cards from the 24 in this chapter.
What is a 'scale' on a map?
A ratio showing how distance on the map compares to real distance. '1 in : 50 mi'.
What is a 'complex unit rate'?
A unit rate involving fractions or decimals. Like 'walking 1/2 mile in 1/4 hour'.
Calculate simple interest on $500 at 4% for 2 years.
$40.
These are a sample. The full Computing Unit Rates with Complex Fractions chapter runs 44 items with per-chapter progress tracking, on the web and in the iOS app.
Open 7th Math: Ratios & Proportional Relationships in CoStudy →
All 7th Math: Ratios & Proportional Relationships practice questions →