She has to buy both binders and notebooks. So, you have to take into account that she has to have both. The closest you can get to $20 while still getting notebooks, is to buy 4 binders. 4 times 4 equals 16. So, she can get 4 binders and 2 notebooks, because then, 2 times 2 equals 4 and 16 plus 4 equals 20.
OK, so for this equation, your goal is to get the d, and ONLY the d, on one side of the equation. So, to start out, you need to multiply the entire equation, meaning both sides, by 8 because we are trying to get rid of those pesky fractions.
8(1/8(3d-2)=1/4(d+5))
The equation then turns into this because the 8 and 4 cancelled out with the 8.
1(3d-2)=2(d+5)
Now, we need to distribute the left over numbers into the parenthesis.
3d-2=2d+10
And finally, we need to get the d's on one side, and the numbers on the other, so we subtract 2d from both sides and add the 2 to both sides. They then cancel out to make
d=12
Hope it helps! :)
(S=D/T)S=216KM, T=8HOURS : 216/8=27KM/HOUR
You posted the question twice ... I have repeated the answer here .. .
Find the area of all the sides:
10 x 9 = 90
9 x 8 = 72
1/2 x 6 x 8 = 24
1/2 x 6 x 8 = 24
6 x 9 = 54
Add them up:
90 + 72 + 24 + 24 + 54 = 264 square metres
12 divided my four is 3. So three is your answer.