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If (2x10^n)+(4.02x10^5), what is n?

asked
User Jass
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9.4k points

1 Answer

2 votes

(2x10^n)+(4.02x10^5), what is n?

Explanation:

To determine the value of n, we need to rewrite the expression as a number in scientific notation, in the form a x 10^n, where 1 ≤ a < 10.

We can start by factoring out 10^n from both terms:

(2 x 10^n) + (4.02 x 10^5) = 10^n (2 + 4.02 x 10^-5)

Now we need to divide both sides of the equation by (2 + 4.02 x 10^-5):

(2 x 10^n) + (4.02 x 10^5) / (2 + 4.02 x 10^-5) = 10^n

We can simplify the expression on the left side by multiplying the numerator and denominator by 10^5:

(2 x 10^n x 10^5 + 4.02 x 10^5) / (2 x 10^5 + 4.02) = 10^n

Simplifying the numerator:

(2 x 10^(n+5) + 4.02 x 10^5) / (2 x 10^5 + 4.02) = 10^n

Now we can cross-multiply to eliminate the fraction:

(2 x 10^(n+5) + 4.02 x 10^5) = 10^n (2 x 10^5 + 4.02)

Expanding both sides:

2 x 10^(n+5) + 4.02 x 10^5 = 2 x 10^(n+5) + 4.02 x 10^n

Subtracting 2 x 10^(n+5) from both sides:

4.02 x 10^5 = 4.02 x 10^n

Dividing both sides by 4.02:

10^5 = 10^n

Therefore, n = 5.

answered
User Bhavik Modi
by
7.9k points
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