Revenue = Profit - Cost
Revenue = [150 + (4/10)P] - 150

P = 150 + (4/10)P
(6/10)P = 150
P = 150(10/6)
P = 250

R = 250 - 150 = 100

this is all about furniture dealer purchased desk

the markup is 50% of the total price, the cost of 140 is 70 percent of the cost
hence the markup is two thirds of 160 = 70*2 =140

I used the options to help me out here, as i was sort of not confident!
let's start with E: 100

s.p - c.p = profit
s.p - 150=100
so s.p = 250 ---1

s.p=150(given:c.p)+100 ---eq2
lets deep dive into this 100 and look at the question " set the selling price equal to the purchase price plus a markup that was 40% of the selling price"
ok, we have the purchase price 150$, plus "40% of the selling price"
"40% of the selling price" we know this equals 100 from equation 2.
100=40% of the selling price, from 1, we know it's 250
100=40% of 250
100=100.. hence proved.. long but works when you are unsure.

Purchase price = $150
let selling price = s

s = $150 + 0.4s
0.6s = 150
s = 250

250 - 150 = $100

Answer is E.
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Selling Price = x

150+0.40x=x

⇒ 0.60x=150

∴ x=250

Profit 250-150=100

The answer is E
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