Answer:
B
Step-by-step explanation:
4(x+3) is 4x+12 and -2(-x-5) is 2x+10 so it makes 4x + 12 + 2x + 10
First, let's assign two variables: one for the name of the limestone statue, and one for the name of the marble statue. 'L' will represent the age of the limestone, and 'm' represents the age of the marble statue.
With the given, we can make two equations:
L = m + 56 (A limestone statue is 56 years older than a marble statue)
L + 12 = 3(m + 12) (In 12 years, the limestone will be three tikes as old as the marble statue)
Thanks to the first equation, we already have a value for L, m + 56.
Input it into the second equation:
(m + 56) + 12 = 3(m + 12)
Simplify:
m + 68 = 3m + 36
Subtract:
68 = 2m + 36
Subtract:
32 = 2m
Divide:
16 = m
Since the limestone statue is 56 years older:
L = 16 + 56 = 72
The marble statue is 16 years old, and the limestone statue is 72 years old.
-T.B.
Step-by-step explanation:
<em>1</em><em>5</em><em> </em><em>6</em><em>0</em><em>0</em><em> </em><em>0</em><em>0</em><em>0</em><em> </em><em>0</em><em>0</em><em>0</em><em> </em><em>centili</em><em>ters</em><em> </em>
Percentage error is calculated by
Percentage error = (estimate-real)/real*100%=(115-82.5)/82.5*100%=28.26%
An over-estimate gives a positive error percent, and an underestimate gives a negative error.
Also, dividing by the real value makes it possible to have more than 100% error.
For example, if real cost is $50, and estimated cost is $150, then error percent is (150-50)/50*100%=200%!