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25 votes
25 votes
Simplify (6.51 x 10^-11)(7.8 x 10^-18). Write the final answer in scientific notation.

User Peterc
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1 Answer

19 votes
19 votes

Answer:

5.0778 × 10^-28

Explanation:

now, after my explanations in your previous questions, you should be able to do this on your own without any problems. right ?

what is it that still causes you a problem ?

again, multiplying multiplications allows us to move and group the operands freely.

and - when multiplying the same base unit, we keep the base unit and add the exponents as new exponent.

(6.51 × 10^-11) × (7.8 × 10^-18) =

= 6.51×7.8 × (10^-11)×(10^-18)

6.51×7.8 = 50.778

-11 + -18 = -11 - 18 = -29

(10^-11)×(10^-18) = 10^-29

we get

50.778 × 10^-29

so, reaching that point should have been easy for you.

now a little extra caviar :

scientific notation means ONE digit left of the decimal point, the other digits right of the decimal point, and then the correctly adapted power of 10.

but we have 2 digits left of the decimal point.

what do we have to do ?

we have to divide the left side of the number by 10 (or multiply by 1/10 or 10^-1) and multiply the right side of the number by 10 (= 10¹) to keep the number in itself unchanged.

50.778 × 10^-29 =

= 5.0778 × 10^-28

User UltraGentle
by
2.9k points