A grocer has two kinds of candies, one selling for 40 cents a pound and the other for $1.40 per pound. How many pounds of each kind must he use to make 100 pounds worth 85 cents a pound?

55 lbs of $0.40 and 45 lbs of $1.40

Step-by-step explanation:

Let's say that we have two buckets, one that weighs x pounds and the candies in it are $0.40 per pound and another that weighs 100-x pounds (because we know the two added together must be 100 pounds) and the candies in it are $1.40 per pound.

There is a third bucket that is made when you combine the two, it weighs 100 pounds and the candies in it are $0.85. Multiply the cents per pound by the pounds of the candy for each bucket and you get this equation:

0.4 * x + 1.4 (100-x) = 0.85 * 100

Solve!

0.4x + 140 - 1.4x = 85

-x + 140 = 85

-x = -55

x = 55

From this we get that 100 - x = 45.

So, the answer is 55 lbs of $0.40 and 45 lbs of $1.40

i think it is 18

step-by-step explanation:

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m