Explanation

Let the original price be P.

The original price (P) minus 30% of the original price (P) equals the discounted price.

P – 30% of P = $105

\(P - 0.30(P) = 105\)

\(0.70(P) = 105\)

\(P = 150\)

Hence option D is correct.
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If we let n = the original price of the calculator, we see that 0.7n is the discounted price. We can create the equation:

0.7n = 105

n = 105/0.7 = 150

Answer: D
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Answer D

Let the original price be X.

If the discounted price was less than 30% of the original price, then the discounted price is 70% of Original price X and is equal to 105$.

We are being asked for the value of original price X.

Since 70% of Original price, i.e. 70% of X = 105,

0.7X= 105

X= 105/0.7

Multiply both numerator and denominator by 10, to bring the denominator to 7 and to make the division easier.

X=1050/7=150

Original price, X=150.

Best Regards,
Ravishankar Nagarajan