To solve this, first we calculate all the total cost of
the items that is:
total cost = $14.96 + $19.87 + $5.37
total cost = $40.20
So we see that the actual cost is similar with the
estimate so his calculation is reasonable.
Answer:
1a
Step-by-step explanation:
8000*0.25=2000
2000*0.25=500
500*0.25=125
...
6-6a=3a-3b+1, 9a-3b=5
<span>4b - 8 =3a, 3a-4b=-8
</span>
9a-3b=5
(3a-4b=-8 )*(-3 )
9a -3b= 5
-9a+12b=+24
adding both equations
9b=29, b=29/9
3a=4b-8=4*29/9 -8=(4*29-8*9)/9 = 44/9
a=44/27
a-b=44/27 - 29/9=44/27 - 29*3/27=-43/27
this is a correct answer, unfortunately they do not have this choice, probably they made mistake somewhere. I even check the solution of equations by substitution values of a and b into equations
3.1415926535 8979323846 2643383279 5028841971 6939937510 5820974944 5923078164 0628620899 8628034825 3421170679