Question

If Bob had 7 apples and Sally took 3, now many are left?

Answer 1

`4`

Explanation:

Use simple subtraction. Imagine seven apples are in front of you:

o o o o o o o

Then pretend three disappeared.

o o o o `cancel("o o o")`

Now count the remaining apples. There are four left over.

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Or you could write this out as a math problem:

`7-3=x`

Do the math using a calculator or write it out.

`7-3 = 4`

Answer 2

Another way of calculating the answer. It is really the same as the other methods. It just looks different.

`7-3=4`

Explanation:

Known: `color(blue)(3+4=7)`

Substitute for 7 giving:

So for `color(brown)(7-3color(blue)(" "->" "3+4)-3 )`

`=>3-3+4" "=" "0+4" "=" "4`