Is this math problem as simple as it looks?
Let’s read the question written on the paper carefully.
Emily was asked her age.
She answered with a math expression: 80 minus 40 divided by 10 multiplied by 4.
How old is Emily?
To solve this problem correctly, we must follow the standard order of operations.
In mathematics, the standard rule is often remembered as PEMDAS or BODMAS.
This rule stands for Parentheses, Exponents, Multiplication and Division, Addition and Subtraction.
When we have both multiplication and division in an expression, we do not always multiply first.
Instead, we perform multiplication and division from left to right as they appear.
Similarly, addition and subtraction are performed from left to right as they appear.
Let’s look at Emily’s expression: 80 – 40 ÷ 10 × 4.
First, we identify the operations in the expression.
We have subtraction (-), division (÷), and multiplication (×).
According to the order of operations, division and multiplication must be done before subtraction.
Since division appears first from the left, we perform 40 ÷ 10 first.
40 divided by 10 equals 4.
Now we replace 40 ÷ 10 with 4 in our expression.
The expression now becomes: 80 – 4 × 4.
Next, we look at the remaining operations: subtraction and multiplication.
Multiplication has higher priority than subtraction.
So, we must calculate 4 × 4 before subtracting.
4 multiplied by 4 equals 16.
Now we replace 4 × 4 with 16 in the expression.
The expression is now simplified to: 80 – 16.
Finally, we perform the last step, which is subtraction.
80 minus 16 equals 64.
Therefore, the final result of the mathematical expression is 64.
So, Emily is 64 years old!
A common mistake that many people make is calculating from left to right without rules.
If someone does 80 – 40 first, they get 40.
Then 40 ÷ 10 gives 4.
Finally, 4 × 4 gives 16.
However, that method ignores the fundamental rules of mathematics.
By strictly following the correct order of operations, we get the true logical answer.
Emily’s clever answer reveals that she is 64 years old.
