Question

976 children are going on a picnic. They will be taken in minibusses. If 25 children can go in one bus, how many buses do they need?

Two children have solved it. Check if they have made a mistake — correct it. Discuss

• 5 + 10 + 10 + 10 + 4
  `25")"overline976`
  – 125
     581
  – 250
     601
  – 250 
     351
  – 250
     101
  – 100 
        X
• 20 + 10 + 4 + 1
  `25")"overline976`
     – 500
       476
    – 250
      266
  –  125
     101
  – 100
        1

Answer 1

In the first solution, the mistake is in the remainder. The remainder should be 1 instead of zero.
In the second solution; the error is in the third and fourth steps of division.
The quotients in those steps should be 5 and 4 as shown below:

      20 + 10 + 5 + 4
`25")"overline976`
   – 500 
     476
  – 250 
     266
  – 125 
     101
  – 100 
         1

If one extra child can be accommodated in one of the buses then we need 39 buses.
Otherwise, we need 40 buses.
Since taking 1 bus for 1 child is not possible so 39 buses will do.