Let’s call the number of gallons of 30% solution “x”. If we mix together 40 gallons and x gallons of solution, we’re going to come out with a total of 40 + x gallons of that 20% solution. Mathematically, this is
40(12%) + x(30%) = (40 + x)(20%)
With the percents as decimals:
40(0.12) + x(0.3) = (40 + x)(0.2)
Simplifying, we have:
4.8 + 0.3x = 8 + 0.2x
Collecting the x terms on one side and the constants on the other:
0.1x = 3.2
And multiplying both sides by 10 to find x:
x = 32
So, you’ll need 32 gallons of 30% solution to yield 40 + 32 = 72 gallons of 20% solution.
Answer:
561
Step-by-step explanation:
an = dn - (a-d)
The difference is 3.
The first term is 12.
an = 3n - (12-3)
an = 3n - 9
Put n as 1, 2, 3, 4, 5 ....22.
3(1) - 9 = -6
3(2) - 9 = -3
3(3) - 9 = 0
3(4) - 9 = 3
3(5) - 9 = 6
...
3(22) - 9 = 57
Add the first 22 terms.
-6+-3+0+3+6+9+12+15+18+21+24+27+30+33+36+39+42+45+48+51+54+57
= 561
Because <span>STVU is an isosceles trapezoid
so SV = TU
</span><span>6x - 5 = 2x + 7
6x - 2x = 7 + 5
4x = 12
x = 3
answer
x = 3</span>
Answer:
809.4cm²
Step-by-step explanation:
Given the following :
Systematic error = 3.8cm (The measured length is always more than the actual length.)
Most probable dimension :
Width = 85.7 cm
Length = 123.5 cm
Hence most probable area of Rectangle :
Area = Length × Width
Area = 85.7cm × 123.5cm = 10583.95 cm²
Dimension due to Systematic error :
Length = (85.7cm + 3.8cm) = 89.5cm
Width = (123.5cm + 3.8cm) = 127.3cm
Area = Length × width
Area = ( 89.5cm × 127.3) = 11393.35cm²
Systematic error of the area :
value of area with Systematic error - Probable value of area :
11393.35cm² - 10583.95 cm² = 809.4cm²
