Level 2 PSLE
The average height of a group of children was 139.4 cm.
When Mr Tan measured and recorded the height of these children, he wrongly recorded one child's height as 181 cm when it should have been 118 cm. As a result, Mr Tan calculated the average height as 142.4 cm. How many children were there in the group?
Level 2 PSLE
The table shows the number of books read by each child in a class of 21 children. One of the numbers in the table is covered by an ink blot. The average number of books read by the children in the class is 6. What is the number covered by the ink blot?
Level 2 PSLE
The table shows the number of books read by each child in a class of 21 children. One of the numbers in the table is covered by an ink blot. The average number of books read by the children in the class is 6. What is the number covered by the ink blot?
Level 3
Some pupils took a Math exam. Their average score was 74.7 marks. One of the pupils' scores was wrongly recorded as 68 marks instead of 86 marks. As a result, the average score was calculated as 73.5 marks. How many pupils sat for the exam?
