Question

1. what is 18 - 9?

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so, -- =

Explanation:

Step1: Identify the subtraction

We need to calculate $18 - 9$.

Step2: Break down 18 for easier subtraction

Rewrite 18 as $10 + 8$.

Step3: Subtract 9 from 10

$10 - 9 = 1$

Step4: Add the remaining value

$1 + 8 = 9$

Answer:

$18 - 9 = 9$

Filling in the blanks (following the breakdown):
$18 - 8 - 1$
$10 - 1 = 9$
So, $18 - 9 = 9$