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%
Answer:
1/r^56
Step-by-step explanation:
Not sure if you did a typo there or what cus 7 x 8 should be 56
Whenever the power of a number is negative, you flip. So r^-7 becomes 1/r^7
Remove the bracket and distribute 8 to the power of 1 and r^7
1 to the power of 8 will still be 1, r^7 x 8 = r ^ 56
The reciprocal of 3/8 would be 8/3 (basically reversing the numbers).
When dividing fractions, you can just multiply the first fraction by the reciprocal of the second fraction instead of dividing by the second fraction.
3/4 ÷ 3/8
= 3/4 × 8/3
Simplifying gives us the final answer:
= 2
Let me know if you need any clarifications, thanks!
The answer to the question is D
