ACT Math · Function notation and transformations
A cell phone plan charges 30 per month for up to 5 GB of data, plus 10 per additional GB beyond 5 GB. What is the monthly cost for 8 GB of…
A cell phone plan charges $30 per month for up to 5 GB of data, plus $10 per additional GB beyond 5 GB. What is the monthly cost for 8 GB of data used?
Answer and explanation
Answer: J: $60
The plan includes GB for $30. Using GB means additional GB, each costing $10, so the cost is dollars, choice J. Choice F ($40) charges for only extra GB. Choice G ($50) charges for extra GB. Choice H ($80) charges $10 for each of the GB, ignoring the included data and the base charge. The extra rate applies only to data beyond the included GB, so subtract before multiplying.
More Function notation and transformations questions
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- Question 55A function is defined by the table below. If the pattern continues, what is f(6)?
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