Start off by stating your facts. You have a maximum of $8.75. We know that each quarter is 25 cents so we multiply 25x26 equaling 650. Yet we need a decimal so it would be $6.50. Each nickel is worth 5 cents so then you would minus $8.75 and $6.50 getting us to $2.25. Now divide it by 5 cents and you should get 45 nickels. You can also do this by stating that 10 nickels is 50 cents and go until you get 45
Answer:
80 hours
Step-by-step explanation:
let d represent doug, let l represent laura
first, set up a system of equations representing the problem:
since doug spent 10 less than twice the hours laura did, and we know that the total amount of hours they spent together is 230:
l=2d+10
d+l=230
then solve:
*first i rearranged the equations so i can solve this system of equations using elimination method*
l-2d=10
l+d=230
*subtract*
3d=240
d=80
so, doug spent 80 hours in the lab
He needs 75 scoops of powder.
Because 10/2= 5, so you would multiply 15 by 5 to get 75