Financial math: what does amortization mean?

Tutoring math, definitions are needed. The tutor shares the definition of amortization.

Amortization schedules and amortization functions are commonly encountered in financial math. What does amortization mean?

amortization: the separation of a loan payment into two amounts:

  1. the payment against principal;
  2. the interest


Hewlett-Packard Business Calculator Owner’s Manual. Corvallis: Hewlett-Packard, 1988.

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

Cooking: oven French fries

Experimenting with cooking is self-tutoring. The tutor discusses making French fries in the oven.

I wanted to make French fries, but don’t have a fryer. I looked up the oven method on the internet.

I admit I didn’t follow any recipe specifically.

Some of the fries I cut too finely, so they burnt up after about 35 minutes. The ones that didn’t burn turned out very well. Put it this way: there were no leftovers.

Going forward, I think cutting the fries 0.5″ square will prevent burning.

For three (very) large potatoes, I use 4 to 5 tablespoons of oil. In a bowl, I toss the cut potatoes in the oil, then salt liberally. I continue tossing, then salt liberally again. Next, I lay the cut potatoes out flat on baking sheets.

I imagine baking them for about 40 minutes at around 450F (232C).



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

Geography: maple syrup production

Tutoring geography, agriculture is topical. The tutor brings up maple syrup production by region.

Of course my kids have this Friday off, so I made them (and myself) pancakes for breakfast. While they actually prefer plain syrup, I like maple syrup on mine.

Which provinces (or states) are notable producers of maple syrup?

  1. Quebec leads (perhaps no surprise): 7,989,000 gallons.
  2. Vermont is next, at about 11% of Quebec’s output.
  3. Ontario comes next, at about 5% of Quebec’s output.
  4. The states of New York and Maine come next, at about 4% each of Quebec.
  5. New Brunswick is next, at 3.8% of Quebec.
  6. Six US states come next.
  7. Nova Scotia follows, at about 0.3% of Quebec.

Interesting, eh?


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

Design: ebony and ivory

Tutoring web design, you encounter color choices. The tutor follows his fascination about off-whites paired with dark colors.

From my research, here is what ebony and ivory look like together:

▮▮▮ Ebony ▮▮▮
▮▮▮▮ and ▮▮▮▮
▮▮▮ ivory:) ▮▮▮



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

Canadian Geography: two Lawrencetowns in Nova Scotia?

Tutoring social studies, the Maritimes enter the conversation. The tutor mentions a discovery he made a couple of days ago about Nova Scotia.

Recently, looking at a map of Nova Scotia, I noticed a place called Lawrencetown, perhaps about 5 miles east of Dartmouth.

“Lawrencetown’s in the Annapolis Valley,” I thought to myself. “It’s northwest of Dartmouth, maybe 50 miles as the crow flies.”

I moved the map around on the web page, and behold! Both Lawrencetowns were apparent – the one in the Annapolis Valley I knew as a kid, as well as the one east of Dartmouth.

I hadn’t known there were two.


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

Lifestyle: apple tree pruning – or lack thereof

Lifestyle tutoring takes the front once again, as the tutor mentions some observations about this season’s apple harvest.

I’m no pruning expert, but I do know some principles about it. Normally I prune the apple tree during winter.

Last year, pruning escaped me. Ironically, part of the reason might have been that we had so much snow, pruning simply couldn’t be done a couple of times I thought of it. When next I contemplated it, leaves were already budding, so I left it.

The growing season put a bumper crop on the apple tree this year: several of its branches sank to the ground, heavy with fruit. I went out to pick them September 18: see my post here.

Harvesting the apples, I noticed some trends which were likely more evident due to my lack of pruning:

  1. The upward-pointing branches didn’t produce any apples – none at all.
  2. In places where the branches were crowded, the apples were thick, but much more likely to be damaged by pests.

Of course, one key mandate of pruning is to eliminate crowding – now I see why. Normally, I would likely have pruned the upward-pointing branches, since they’re harder to pick apples from anyway.

BTW: the apples aren’t all picked yet, but most have been. They’re not falling off yet.

I must remember to prune this winter:)

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

Geography: UTM coordinates

Tutoring math, number-oriented topics naturally arise. The tutor gives some simple points about the UTM coordinate system.

UTM stands for Universal Transverse Mercator: it produces a grid on Earth from which locations can be referenced.

UTM organizes the Earth, from the International Date Line towards east, into 60 zones, each six degrees wide. The zones are numbered 1 to 60; here, in Campbell River, we’re in zone 10.

From the South Pole to North Pole, there are reference lines lettered C to X that suggest latitude.

The numbers, going east, and the letters, going north, make a grid. Here in Campbell River, we are in square 10U.

The north (or south) coordinate of UTM is absolute, measured from the equator; the east coordinate, however, is measured relative to the zone the location is in.

Coordinates are measured in metres. Possibly confusing, the east reference point of a zone is located 500,000 metres (500km) west of its centre. Since the zones are less than 1000km (1,000,000m) wide, an east coordinate of zero will never happen. If a zone is 400km wide (they get narrower as you go north, since they converge at the equator), the east coordinate of a location within it could be from 300,000 to 700,000.

Since the north (or south) coordinates are absolute, the letter of the UTM grid square is not always used. Campbell River is in square 10U, but its coordinates might be given zone 10, E:337,196 N:5,544,789.

That’s UTM as I understand it.



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

Homework: how much per night?

Tutoring, you might wonder about minutes of homework per night. The tutor shares some findings.

I’ve heard a rule of thumb that the suggested amount of homework per night is grade times 10. Therefore, a grade 8 student can expect 80 minutes per night, and a grade 12, 120 minutes.

What I’ve seen published, for homework guidelines, is as follows:

K-3: none.

4-7: 1/2 hour per night.

8-12: 1 to 2 hours per night.

Of course, the amount of homework from one night to another can vary considerably. Furthermore, my grade 8 child seldom does homework, while my grade 10 certainly does an hour some nights.


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

Spreadsheets: p-value with Excel

Tutoring stats, you deal with p-values. The tutor shows an Excel connection.

In my posts here and here I mention p-values.

Example: Using Excel, get a two-tailed p-value for z=2.4

Solution: Using symmetry, it’s best to get the cumulative z-probability for -2.4, then double it:


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

Biology: what is a trophic level?

Tutoring biology, you come across the concept of trophic level. The tutor defines it.

In an ecosystem, a tropic level can be thought of as a level of energy or of consumption.

The organisms at trophic level 1 are called primary producers. By photosynthesis, they harvest energy from the sun to produce carbohydrates. Grass is a primary producer; in the ocean, phytoplankton is an example.

At trophic level 2 are the plant-eaters.

At trophic level 3 are predators (carnivores).


Mader, Sylvia S. Inquiry into Life, 9th ed. Toronto: McGraw-Hill, 2000.

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