It is: 120 people
50% increase.
60% solution contains 6/10 x 30 ie 18 litres 18 + A = 3/4 (30 + A) 72 + 4A = 90 + 3A 4A - 3A = 90 - 72 A = 18 ie add another 18 litres, giving 36 litres out of 48 which is the required 75%.
At first glance the question seems not to have enough information. Thinking about it, there is enough information for some general observations. 78 percent is quite a large proportion of a population. For example, if a US president won with 78 percent of the popular vote, that would be a breathtaking landslide by anyone's reckoning. If 78 percent of a random population were male, or were female, that would be seriously outlandish and an indication that something is seriously wrong. If 78 percent of a sample of 500 people had recorded IQ's of 100 or better given the generally understood mean and s.d. of IQ, then that would be very strong evidence that the population was not chosen randomly. Apart from this general kind of observation, 78 percent is virtually meaningless unless you give the number out of which you are isolating the 78 percent. For example, 78 percent of a sample of 100 people would be 78 people. 78 percent of the world's population would be considerably larger than that.
The total volume of solution equals 18 L. So if we let X be the 50% solution & Y be the 20% solution we can solve a set of two equations with 2 unknowns: X + Y = 18 (total volume of solution is 18 L) 0.5X + 0.2Y = 18*(0.30) (the total amount of alcohol in the new 18L solution) Solving simultaneously, multiply the 1st equation by 0.5 then substract to solve for Y. X + Y = 18 {*0.5} => 0.5X + 0.5Y = 9 0.5X + 0.2Y = 5.4 => 0.5X + 0.2Y = 5.4 ------------------------------------------------------- 0.3Y = 3.6 Y = 12 Then substitute for Y back into the 1st equation & solve to get X=6. So you need 12 L of the 20% solution & 6 L of the 50% solutions to mix together to get 18 L of a 30% alcohol solution.
1.2825 billion
18 percent of the world's population would be approximately 1.4 billion people.
18 = 1,800%
A. 16 of 18 percent and 2 of 9 percent b. 14 of 18 percent and 4 of 9 percent c. 16 of 9 percent and 2 of 18 percent d. 14 of 9 percent and 4 of 18 percent
12.5% is NOT greater than than 18%.
Reading and writting.
18
18
18 percent of 30 is 5.4
I think 15% to 18% percent but I not sure
18 = 1,800 percent.
18 to a percent = 1800% 18 * 100% = 1800%