Consider the number 50,540.We have to determine the significant figure.
Significant figures are the digits that carry meaning contributing to its measurement resolution. It excludes the leading and trailing zeroes.
The first zero in the 50 is considered to be a significant number, while the second zero (in the 540) is not significant number.
The second zero is a called a placeholder zero. It can be removed by converting the number into scientific notation.
When ever you have percentages, it should be helpful to bear in mind you can express them as multipliers. In this case, it will be helpful.
So, if we let:
a = test score
b = target score
then, using the information given:
a = 1.1b + 1
a = 1.15b - 3
and we get simultaneous equations.
'1.1' and '1.15' are the multipliers that I got using the percentages. Multiplying a value by 1.1 is the equivalent of increasing the value by 10%. If you multiplied it by 0.1 (which is the same as dividing by 10), you would get just 10% of the value.
Back to the simultaneous equations, we can just solve them now:
There are a number of ways to do this but I will use my preferred method:
Rearrange to express in terms of b:
a = 1.1b + 1
then b = (a - 1)/1.1
a = 1.15b - 3
then b = (a + 3)/1.15
Since they are both equal to b, they are of the same value so we can set them equal to each other and solve for a:
(a - 1)/1.1 = (a + 3)/1.15
1.15 * (a - 1) = 1.1 * (a + 3)
1.15a - 1.15 = 1.1a + 3.3
0.05a = 4.45
a = 89
Akim ran 69.75 miles in the course of 18 days.
A parallelogram with congruent diagonals is a
.. B - rectangle.
The quantities in the proportion you give add to 16 pounds, of which 2 pounds are cement. That is, cement constitutes 1/8 of the total weight.
For each yard of concrete, 4000 lb/8 = 500 lb of cement are used.
For 12.5 yards of concrete, 12.5 * 500 = 6,250 pounds of cement will be used.
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"yard" in this case is shorthand for "cubic yard".