Tutoring high school math, scientific calculators are a permanent fascination. The tutor mentions a quirk many might share.

Due to

and the fact that a common exponent notation is

xa=x^a,

it follows that

(-8)^(2/3)=4.

Curiously, of all the calculators in front of me this moment, only two – the Casio fx-991ES PLUS C and the TI-83 Plus (a graphing calculator) – are willing to perform (-8)^(2/3) as presented. The others give “ERROR”.

Yet, invoking the rule shown above, we can rewrite the calculation as

3√(-8)2

Then, all the scientific calculators I have at hand will give the answer 4. However, the calculator aboard my mobile phone will only do so if the square is posed before the cube root.

HTH:)

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC

Tutoring math, scientific calculators are always interesting. The tutor mentions changing between DEG and RAD mode on the Media SC-1000.

The Media SC-1000 is an appealing scientific calculator. I’ve been using it often during my sessions lately, having bought one years ago.

To move into RAD mode from DEGREE mode (or back the other way), do the following:

1. Press the MODE CLR button twice, at which time you’ll hopefully see the choice for Deg, Rad, or Gra.
2. Select which of Deg, Rad, or Gra you wish.

HTH:)

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Tutoring math, calculators can always be interesting. The tutor shares a capability of the Nexus 4 on-board calculator.

If the Nexus 4 on-board calculator has broad complex number capabilities, I don’t know about them. I tried √(-4) and got Not a number.

Yet, behold!

Neat, eh?

Source:

Wikipedia

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Tutoring math, you notice the peculiarities of scientific calculators. The tutor brings up one about the Casio fx-991ES PLUS C.

If you enter the operation 14÷9 into the Casio fx-991ES PLUS C, you’ll just as likely see 14/9 on the screen. If you want the decimal, just press the S⇔D key.

You can keep pressing the S⇔D key to toggle through various formats of the answer.

HTH:)

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Tutoring math, you come to appreciate calculators. The tutor points out an interesting feature on the Casio fx-991ES PLUS C.

Typically, the log key on a calculator means “base 10 log”, aka “common log.” What about base 7 log, for instance?

The Casio fx-991ES PLUS C has a log□ key which can accept an input for the base.

Example: On the Casio fx-991ES PLUS C, evaluate log762.

Solution:

1. Press the log□ key, second down on the right.
2. Press 7, then arrow over once, then key 62, then arrow out of the brackets.
3. Press =

Everyone not blessed with the Casio fx-991ES PLUS C can just enter log62/log7 =

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Tutoring math, calculator features are always topical. The tutor mentions the ENG function on the Casio fx-991ES PLUS C.

Back in my Halloween, 2015 post, I explain the general idea of the ENG function – that engineers and technicians often like to refer to measurements in “thousand” groupings. For instance, 1249W is 1.249kW; 0.067A is 67mA.

Example: convert 0.78A to mA

1. Key 0.78 = (you must press = for this to work)
2. Press ENG: hopefully you see 780×10-3

Example: convert 1249W to kW.

Solution: to go up to the bigger unit, use SHIFT ENG, like so:

1. Key 1249 = (once again, you must press =)
2. Press SHIFT then ENG. Hopefully you see 1.249×103

HTH:)

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Tutoring financial math, you might often use the HP-10B. The tutor shows how easily it can apply a discount then add tax to get the final price.

Example: Imagine a handbag is regular price \$85 but is discounted by 20%. Assuming 12% sales tax, find final price using the HP-10B.

Solution:

1. Key in 85
2. Key in – 20 % =
3. Key in + 12 % =

HTH:)

Source:

Hewlett-Packard HP-10B Business Calculator Owner’s Manual. Corvallis: Hewlett-Packard, 1994.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Tutoring financial math, you might fall in love with a calculator. The tutor tells about markup on the HP-10B.

Example: Imagine you buy a product for \$35, then want to apply a 25% markup. Find the tag price using the HP-10B.

Solution:

1. Key in 35 then CST
2. Key in 25 then the orange key then MAR
3. Press PRC

HTH:)

Source:

Hewlett-Packard HP-10B Business Calculator Owner’s Manual. Corvallis: Hewlett-Packard, 1994.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Tutoring financial math, you’ll likely encounter the capable HP-10B. The tutor tells how to use its user-accessible memory.

The HP-10B seems to have 11 dedicated places to store your own numbers. The locations are at 0 to 9, plus there is the M register.

Example: On the HP-10B, store the number 65.21 in register 5.

1. Key in 65.21
2. Press the orange key
3. Press RCL
4. Press 5

To retrieve the number,

1. Press RCL
2. Press 5

HTH:)

Source:

Hewlett-Packard Business Calculator HP-10B Owners Manual. Corvallis: Hewlett-Packard, 1994.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Tutoring math, you see all kinds of scientific calculators. The tutor continues to praise the Casio fx-991ES PLUS C.

If you were to be marooned on an island with a single calculator…which one would you prefer? The question is absurd, of course. Yet, I believe I know my answer: the Casio fx-991ES PLUS C. It has seemingly endless functionality for a little scientific calculator.

Today I noticed that it calculates binomial pdf.

Example: Using the Casio fx-991ES PLUS C, find the probability of 20 successes in 35 trials when p=0.44.

Solution:

1. Press MODE, then arrow down
2. Select 3
3. Select 4
4. For a single query, select 2
5. It will ask for x (the number of successes). Key in 20 =
6. Next, it will ask for N (the number of trials). Key in 35 =
7. Now it will ask for p (the probability of success each time). Key in .44 =