We can first find the total number of quizzes and the number he got them right:
Total number: 20+80=100
Total correct answer:
20×60%+50×80%
=52
We can then find the percentage:
Therefore the answer is 52%.
Hope it helps!
50 days is how long the 40 pounds of dog food will last
Half of the bag of dog food(20 pounds) will last 25 days.
You substitute in an expression by filling in the desired and accustomed unknown value to the value you're trying to find. An example below can better elaborate what I want to say above. In the equation below, 7 - 2n = 5 the unknown is represented by n moreover, the equation suggest to find the missing to make it equilateral on both sides.
In mathematical expression, the equation then becomes 7 - 2n = 5
The next procedure is to find the unknown.
1. 7 - 2n = 5
2. -2n = 5 - 7
3. -2n = -2
4. n = -2/-2
5. n = 1
Check:
Substitute n = 1
7 - 2 (1) = 5
7-2 = 5
5=5
The answer for 3x/6+1=7 is 12
