one fifth of a plank is sawn off and there eights of the remaining peice is then thrown away. What fraction of the original plank remains?
after 1/5 gone, there are 4/5 remaining.
3/8 * 4/5 = 3/10
So, what remains is 1 - 1/5 - 3/10 = ______
Correction:
1 - 1/5 = 5/5 - 1/5 = 4/5 remaining.
4/5 - 3/8*4/5 = 4/5 - 12/40 = 32/40 - 12/40 = 20/40 = 1/2 remains.
1 - 1/5 = 5/5 - 1/5 = 4/5 remains.
4/5 - 3/8 = 32/40 - 15/40 = __ remains.
To find the fraction of the original plank that remains, we can follow these steps:
1. Start with the whole plank, which can be represented by the fraction 1/1.
2. Cut off one-fifth of the plank. One-fifth can be represented by the fraction 1/5. To find the remaining portion, subtract 1/5 from 1/1:
1/1 - 1/5 = 5/5 - 1/5 = 4/5
3. After cutting off one-fifth, there are 4/5 of the original plank remaining.
4. Now, we need to throw away one-eighth of the remaining plank. One-eighth can be represented by the fraction 1/8. Subtracting 1/8 from 4/5:
4/5 - 1/8 = 32/40 - 5/40 = 27/40
5. After throwing away one-eighth, there are 27/40 of the original plank remaining.
Therefore, the fraction of the original plank that remains is 27/40.