## Home economics: Mr. Market, part0

Self-tutoring about grocery shopping and economics: the tutor begins…. In my family, I do a fair amount of the grocery shopping – it’s something I’ve been learning since around 2017. With grocery shopping, it’s hard to imagine the learning will …

## Lifestyle: toy repair with J-B Weld, part II

The tutor continues about a toy repair, with some reinforcement ideas. While we were repairing the toy a few nights ago (see my previous post), my father-in-law suggested that, after the first repair cured, a second application should be considered …

## Lifestyle: toy repair w/ J-B Weld

The tutor wonders about a pending toy repair. My younger son has a toy he really loves that broke. Specifically, a pot metal part sheared off. It’s a toy out of production, so can’t be replaced. Looking at the breakage, …

## Spreadsheets: Excel circular reference: recursive deduction calculation

The tutor shows how to use a spreadsheet (Excel) to compute a recursive deduction rate using a circular reference. In yesterday’s post I brought up an example in which a deduction depends upon the income minus that same deduction. It’s …

## Math: Deduction rates: a recursive example

Sometimes, deduction rates can be tricky. The tutor offers an example of a “circular argument.” Let’s imagine a benevolent employer offers a health plan that costs 6% of the employee’s net income. The company’s definition of net income is gross …

## Spreadsheets: using names in formulas

The tutor shows an example of naming items in a spreadsheet for use in a formula. This post focuses on Microsoft Excel; hopefully I’ll do a similar one for a generic spreadsheet soon. Let’s imagine Jones faces two tax rates: …

## Lifestyle: the Hydro bill

The tutor investigates higher household usage over last year. For Nov11-Jan11, our daily household usage this year was 6kWh above last year. My wife points to the new electric fireplace downstairs as the culprit. More specifically, she means that it’s …

## Financial math: can time be negative?

The tutor answers a question that brought someone to his site. These days, Oracle Tutoring gets between 5000 and 6000 distinct visitors per month. Looking over the raw log entries of how some visitors arrived, I saw an inquiry yesterday …