They are essentially asking us to solve:

Solving this equation for x tells us that it will take around 80.1 years for the materials in the vault to reduce to 357 pounds.
To find a number 10 times smaller than 62 simply move the decimal point one place to the left.
The decimal point in 62 is at the end of the number. 62. becomes 6.2 if we move the decimal one place back.
Answer:
ok....
Step-by-step explanation:
Answer:
C. x + 9 = 11
Step-by-step explanation:
We are trying to identify which of the equations does not match with the others. In this case, solve for x in each equation:
Option A):
6 + x = 9
Subtract 6 from both sides:
6 (-6) + x = 9 (-6)
x = 9 - 6
x = 3
Option B):
15 = x + 12
Subtract 12 from both sides:
15 (-12) = x + 12 (-12)
15 - 12 = x
x = 3
Option C):
x + 9 = 11
Subtract 9 from both sides:
x + 9 (-9) = 11 (-9)
x = 11 - 9
x = 2
Option D):
7 + x = 10
Subtract 7 from both sides:
x + 7 (-7) = 10 (-7)
x = 10 - 7
x = 3
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As you can tell, all the equations end with x = 3 as there answers except C. x+9=11, making (C) your answer.
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Answer:
11.4
Step-by-step explanation:
So we know that Triangle ACB is similar to Triangle EFD.
This means that their sides are proportional to each other.
We want to find x or side AB. To do so, we can set up a proportion.
The proportional side to AB is ED. Let's also use BC since we know its value. The proportional side to BC is DF. Thus:

Substitute x for AB, 3.8 for Ed, 15 for BC, and 5 for DF. Thus:

Reduce the right:

Cross multiply:

So, the value of x is 11.4
And we're done!