# Calculators

Last verified on April 29, 2021

Candidates have two calculator choices for the Part 1 Exam and the Part 2 Exam (MP General and Clinical, MP Clinical only, MP Nuclear, MP Therapy, and MP Diagnostic Exams). No calculator is needed for the Part 3 Exam (Oral).
Candidates may have a Texas Instruments TI-30XS calculator with them during the exam. The calculator must be that specific model. Although Texas Instruments makes a variety of calculators, only the TI-30XS will be accepted.
If a candidate is unable to obtain the required calculator, there is a calculator embedded in the exam interface. The embedded calculator is different from the TI-30XS.

To get familiar with the operation of the embedded calculator, please use the practice exam link in myABR. Once you have registered for the exam, a link to the practice exam will appear on your Cognitive Expertise page. If you have not registered for the exam, you can download the calculator as a Chrome extension here: Chrome Scientific Calculator.
No notes, including manually programmed formulas, will be allowed in the testing area. If the calculator has notes and/or formulas printed on it, or includes any other information, it must be removed or covered by solid colored tape.
As has always been the case, absolutely no other personal electronic, computing, or calculator devices are permitted in the exam area. If you are unable to purchase a handheld calculator, it may be helpful to download the Chrome extension prior to the exam, so you can practice with it.

## Exercises for calculator practice

The following exercises are not indicative of actual questions on the ABR exam. They are intended to help candidates practice with the calculator. Candidates are encouraged to try other examples of calculations that would arise as a routine part of their daily work.
•   Use of ln function:
Calculate the decay constant of 99mTc from its half-life of 6.02 hr.
•   Use of Sin function:
What is the value of the first spherical Bessel function (sin(x)/x) at 0.25 radians? This is also sometimes called the sinc function.
•   Use of Hyperbolic functions:
The Gateway Arch in St. Louis is famous as an inverted catenary that is given by y=693.9 – 68.8 cosh (0.01x). When x=100 ft., what is the value of y?
•   Finding cube roots:
The sensitivity of a photomultiplier tube is often approximated as a cos3 θ function. If the relative sensitivity of the tube is 0.90, what is the effective angle θ in radians?
•   Exponential function:
An 86-MBq source of 99mTc is allowed to decay for 14.6 hrs.  At the end of that period, what will its activity be?
•   Exponential function and use of memory:
A 99Mo/ 99mTc generator is eluted at time zero. This reduces the activity of 99mTc in the generator to zero. If the activity of 99Mo in the generator at time zero is 861 MBq, what will the activity of 99mTc be at 4 hrs? (The half-life of 99Mo is 67 hrs. Use the Bateman equations.)