Answer:
In total 5 packets of rubber bands are needed.
Out of which 5 rubber bands are left.
Step-by-step explanation:
The number of rubber bands needed by 1 student = 5
The total number of students = 8
So, the total rubber bands needed by all students
= Total students x Number of rubber bands needed by 1 student
= 8 x 5 = 40 bands
Now 1 packet of rubber bands = 9 bands
⇒ 2 packets = 2 x ( 9 bands) = 18 bands
⇒ 3 packets = 3 x ( 9 bands) = 27 bands
Similarly, 4 packets = 36 bands , 5 packets = 45 bands
Now, if we buy 4 packet of bands, there are 36 rubber bands which are LESS THAN THE TOTAL STUDENTS.
So, we buy 5 packets.
We have in total 45 bands, but the total students = 40
So, the number of left rubber bands = Total bands - Total students
= 45 - 40 = 5
Hence, in total 5 packets of rubber bands are needed, and out of which 5 rubber bands are left.
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