Arrange $0.19$0.19, $0.392$0.392, $0.499$0.499 and $0.278$0.278 in ascending order.
Arrange the following decimals in descending order:
$8.402,8.204,8.024,8.42,8.24$8.402,8.204,8.024,8.42,8.24
Review of the idea of a decimal fraction, place value in the context of decimal fraction, inter conversion of fractions and decimal fractions (avoid recurring decimals at this stage)