Answer:
120cm
Step-by-step explanation:
168/7=24
24x5=120cm
Explanation is in the file
tinyurl.com/wpazsebu
Step 1. Simplify
7x^2 - 8x - 4 - 2x^2 + 3x + 5 + 5x^2 - 10x - 8
Step 2. Collect like terms
(7x^2 - 2x^2 + 5x^2) + (-8x + 3x - 10x) + (-4 + 5 - 8)
Step 3. Simplify
10x^2 - 15x - 7
There are 32,760 different orders for the first four positions.
This is a permutation where repetition is not allowed; the formula for that is:
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For our problem, we have: