PSAT/NMSQT Prep 2022 - Eggert M.D., Strelka A. 2022
Calculator use
Prerequisite skills and calculator use
PSAT math
LEARNING OBJECTIVE
After this lesson, you will be able to:
· Distinguish between questions that need a calculator and questions in which manual calculations are more efficient
Calculators and the PSAT
Educators and parents believe that calculators serve a role in solving math questions, but they are sometimes concerned that students rely too heavily on calculators. They believe this dependence weakens students’ overall ability to think mathematically. Therefore, the PSAT has a policy on calculator use to promote the idea that students need to be able to analyze and solve math questions both with and without a calculator. The first math section you see will require you to work without a calculator, while the second math section will allow you to use one.
Many students never stop to ask whether using a calculator is the most efficient way to solve a problem. This chapter will show you how the strongest test takers use their calculators strategically; that is, they carefully evaluate when to use the calculator and when to skip it in favor of a more streamlined approach. As you will see, even though you can use a calculator, sometimes it’s more beneficial to save your energy by approaching a question more strategically. Work smarter, not harder.
Which Calculator Should You Use?
The PSAT allows four-function, scientific, and graphing calculators. No matter which calculator you choose, start practicing with it now. You don’t want to waste valuable time on test day looking for the exponent button or figuring out how to correctly graph equations. Due to the wide range of math topics you’ll encounter on test day, we recommend using a graphing calculator, such as the TI-83/84. If you don’t already own one, see if you can borrow one from your school’s math department or a local library.
A graphing calculator’s capabilities extend well beyond what you’ll need for the test, so don’t worry about memorizing every function. The next few pages will cover which calculator functions you’ll want to know how to use for the PSAT. If you’re not already familiar with your graphing calculator, you’ll want to get the user manual; you can find this on the Internet by searching for your calculator’s model number. Identify the calculator functions necessary to answer various PSAT Math questions, then write down the directions for each to make a handy study sheet.
When Should You Use a Calculator?
Some PSAT question types are designed based on the idea that students will do some or all of the work using a calculator. As a master test taker, you want to know what to look for so you can identify when calculator use is advantageous. Questions involving statistics, determining roots of complicated quadratic equations, and other topics are generally designed with calculator use in mind.
Other questions aren’t intentionally designed to involve calculator use. Solving some with a calculator can save you time and energy, but you’ll waste both if you go for the calculator on others. You will have to decide which method is best when you encounter the following topics:
· Long division and other extensive calculations
· Graphing quadratics
· Simplifying radicals and calculating roots
· Plane and coordinate geometry
Practicing long computations by hand and with the calculator will not only boost your focus and mental math prowess, but it will also help you determine whether it’s faster to do the work for a given question by hand or reach for the calculator on test day.
Graphing quadratic equations may be a big reason you got that fancy calculator in the first place; it makes answering these questions a snap! This is definitely an area where you need to have an in-depth knowledge of your calculator’s functions. The key to making these questions easy with the calculator is being meticulous when entering the equation.
Another stressful area for many students is radicals, especially when the answer choices are written as decimals. Those two elements are big red flags that trigger a reach for the calculator. Beware: not all graphing calculators have a built-in radical simplification function, so consider familiarizing yourself with this process.
Geometry can be a gray area for students when it comes to calculator use. Consider working by hand when dealing with angles and lines, specifically when filling in information on complementary, supplementary, and congruent angles. You should be able to work fluidly through those questions without using your calculator.
If you choose to use trigonometric functions to get to the answer on triangle questions, make sure you have your calculator set to degrees or radians as required by the question.
To Use or Not to Use?
A calculator is a double-edged sword on the PSAT: using one can be an asset for verifying work if you struggle when doing math by hand, but turning to it for the simplest computations will cost you time that you could devote to more complex questions. Practice solving questions with and without a calculator to get a sense of your personal style as well as your strengths and weaknesses. Think critically about when a calculator saves you time and when mental math is faster. Use the exercises in this book to practice your calculations so that by the time test day arrives, you’ll be in the habit of using your calculator as effectively as possible.