Question

Using the properties of integers, find the value of the following -195×(-53)+(-195)×(23)

Answer 1

Answer:

Consider the case in which customers 0-1 were waited on. 1-0 = 1, because you're "not counting" one of the ends. 1-0 + 1 = 2, the correct answer. – vroomfondel Sep 4 '13 at 23:06

13

Use smaller numbers. How many numbers are there from 77 to 1010 inclusive? There are 44, you can list them. This is 11 more than 10−710−7. – André Nicolas Sep 4 '13 at 23:07

16

Because if you don't add 1, you are left with 52, which is not the correct answer. – Kaz Sep 5 '13 at 4:10

13

In my country, we learn this at elementary school. – sawa Sep 5 '13 at 6:52

24

It's sad to see "add 1 to counting test problems" being taught as one of those "rules"... – ithisa Sep 5 '13 at 13:49

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If you don't add 1, then you're saying "take the first 201 customers, but then exclude the first 149 ones." That would give you the number of customers in the list from 150-201.

The way I think of it is this: The number of customers from #149 to #201 is 201−148=53201−148=53, because it's the first 148 customers we're trying to exclude.

Does that help?

Answer 2

Answer:

$- 195 \times ( - 53) + ( - 195) \times 23 \\ \\ = - 10189$

Here is the correct answer mate...

Thank you ☺✌...