How do I solve this using the second method (subtract the whole numbers first): 4 3/7 - 2 4/7?

This isn't a memorization technique, but you could try doing binary subtraction, then afterwards check whether you have got the correct answer by converting the numbers to decimal and then...

As a simple example, let's say we're subtracting ¾ from 1. Convert 1 to 4/4. 4/4 - ¾ = ¼. If the whole number is something else, let's say 6,...

First change 2 3/4 to 2 9/12. Then change that to 33/12. Then subtract 11/12. That gives us 22/12. Change that to 1 10/12, and reduce to 1 5/6.

First convert all three numbers to fractions with 24 as the denominator (because 24 is the lowest common multiple of 2, 12, and 8). 2½ = 60/24. 5/12 = 10/24....

It tells you that second hygrometer is accurate and your room is at 40% relative humidity. It also tells you need to calibrate the first one.

There are a very few models from manufacturers like Samsung that still offer this feature. However, this feature is now rare.

You can use the whole vanilla bean, but it won't dissolve. The oils will infuse into the milk, but the bean will remain whole for you to pull out afterward....

An ellipsis in this situation indicates omitted content, and it doesn't discriminate. You can safely remove the semicolon: "A river watering the garden flowed from Eden..." Though you could also...

No. You'll have to write very small on the top line.

You will only need 5 numbers. Repeating the same numbers over again will make for a simple 'Bingo' and make the game much easier to manage than I personally find...