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The easiest way to prove equivalence is to draw out a truth table and then compare the values. I'm going to show a truth table using proposition logic, it's the same result as using predicate logic.
P(x) v Q(x)
P |Q || PvQ || ~Q->P <----Notice how this column matches the PvQ but if you were to
---|---||--------||---------- <----continue the truth table with ~P->Q it would not be equivalent
T T T T
T F T T
F T T T
F F F F
Let me know if you would like an example, if the truth table doesn't help.
You need to use basic algebra for this.
For this I’ll use o as the items and p for the payment. First you need to find out how long it took for all the items to scan, so if it took each item 2 seconds to be scanned you need to times the total number of items (o) by two e.g. o x 2 = 62 items times two seconds which is equivalent to 62 seconds (1.02 minutes) after this step you need to minus the total time it took to scan the items for the transaction time (2 minutes) e.g. 2.00 - 1.02 = 2.58 minutes.
Hope this helped :)
A lot, 1:6 + 3:4 +3 = .116789465 hope this helps....
