Last month, lana sold 35 necklaces a week at $15 each. however, throughout the month, 6 customers returned their necklaces for a full refund due to defective clasps. how much did lana make selling necklaces last month? (hint: assume there were 4 weeks in the last month.)

35 necklaces multiplied by 4 weeks is 140. Multiply 140 by 15, representing the amount of money each necklace costs and you get 2,100. That is the total amount sold, but because the 6 costumers brought their necklaces back, you have to take 6 times 15 to see how much the total returned necklaces cost. That would be $210, so you take $2,100 and subtract $210, and your answer is $1,180. That is the final answer.

Planet earth has a mass of 5.9726x10²⁴ kg.then: 5.9726x10²⁴ kg=100% of the total earth mass.if the water´s mass=5x10-4 % of the total mass, we can solve this problem by the rule of three.5.9726x10²⁴ %*10⁻⁴ %x=(5.9726x10²³ kg)(5*10⁻⁴  %) / 100 %=2.9863x10¹⁹ kganswer:   the mass of the planet´s water would be   2.9863 x 10¹⁹ kg.