V=LWH
SA=2(LW+LH+WH)
V=240
first check that they are 240 volume
multiply numbers they should equal 240
the first one (A) can be eliminated since the dimentions are the same and therefor the surface areas are the same
2nd one check so far
3rd one (C) 6*4*15=360 which is wrong so eliminate this one
4th (d) 12*6*5=360 which is not 240 so eliminate
answer is B
If Alexa's mom paid 1/2 of the $450:
$65
if Alexa's mom paid 1/2 of the remaining price:
$145
Alexa's mom paying 1/2 the $450:
$450 divided by 2 = $225
$225 - $120 = $105
$105 - $40 = $65
Alexa has $65 left to pay
Alexa's mom paying 1/2 of the remaining price after the student discount and Alexa payed $120:
$450 - $120 = $330
$330 - $40 = $290
$290 divided by 2 = $145
(hope this helped )
The answer you are looking for is -11/10 or - 1 1/10.
To find this answer you must first make the denominators the same. To do this, multiply 2/5 by 2/2 to get 4/10. Finally, subtract the two fractions, keeping in mind the denominators stay the same. -7/10 - 4/10 = -11/10 or - 1 1/10.
I hope this helps!