Answer:amount read at night =4/15
Explanation:
Step 1
Since we are dealing with fractions,
Let Total amount of book contained to read = 1 whole
Therefore
Amount read in the morning + amount read at night +amount remaining = Total amount of book contained to read which gves us the equation
1/3 + x + 2/5 = 1
Step 2 --- solving
1/3 + x + 2/5 = 1
1/3 + 2/5 + x= 1
5 + 6 / 15 + x = 1
11/15 + x= 1
x= 1 - 11/15
15/15 - 11/15
x = amount read at night =4/15