The answer is three it is just asking how many times does 15 occur
Answer:
x=1
Step-by-step explanation:
55x< 200 - 65 is the correct answer Answer : 55 is less than 200 minus 65
Let x be the volume (liters) of pure (at 100%) acid needed
Let y be the volume (liters) of the other acid (at 10%) needed
The final solution will be:
a) x+ y = 63 liters, AND their respective concentration in acid: is
100% x & 10% :y that will generate 63 liters at 20%
b) x +0.1 y = 63x 0.2 = 12.6
Let's solve this system of 2 equations:
x + y =63
x + 0.1 y = 12.6
Solving it will give you:
x= 7 liters at 100%
y = 56 liters at 10%
One way is to make them all decimals or all fractions:
.5 .2 .35 .48 .80 are the numbers above changed to decimals.
I will make them the same length (two digit past the decimal point) to compare
.50 .20 .35 .48 and .80
Now it is easy to put them in order
.2 .35 .48 .5 and .80
Let's put them into all fractions
5/10 1/5 35/100 12/25 and 4/5
Instead of finding a common denominator let's try this:
Think of them as test scores - the person who got 1 out 5 did the worst
Next came the person who got only 35 out of 100 - they only did better than the one above (1/5)
12/25 is almost 1/2 but a little below half the questions right
5/10 is exactly half the questions right (so it is bigger than 12/25 by a little).
4/5 is the best score (and the only one who passed).
So 1/5, 35/100, 12/25, .5 and 4/5 are in order least to greatest and match the answer above in bold.
