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3 years ago

Describe a way to make the arithmetic problem 45% x 680 mentally

Mathematics

1 answer:

lord [1]3 years ago

5 0

Answer:

306.

Step-by-step explanation:

Firstly, we are aware 100% of 680 is obviously 680,

Next, we know half of a 100% is 50% therefore half of 680 is 340.

Then, we know 45% is 5% less than 50%

To find 5% of a number mentally, divide it by 10 as 100÷5=20

680÷20=34

Lastly 50% subtracted by 5%: 340-34=306.

Now we know, 45% of 680 is 306.

<em>Hope this helps.</em>

<em>Hope this helps.Please mark BRAINLIEST.</em>

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