Answer:
We need to start with 5 kg of mushrooms
Step-by-step explanation:
The total of the dried mushrooms = mushrooms * percentage of weight kept
percentage of weight kept = 1- 80% = 20 %
We want 1 kg of dried mushrooms. Substitute in what we know
1 kg = mushrooms * 20%
1 kg = mushrooms * .2
Divide each side by .2
1 /.2 = mushroom *.2 /.2
5 kg = mushrooms
Based on your comment I assume you want to find 7,533 subtracted by 7,200. To estimate this, round 7,533 to the hundreds place, so 7,533 becomes 7,500.
7,500 - 7,200 = 300, using mental math.
the answer is b. y = 20x + 30
