![]() Percentages represent a value out of 100, and any. When ratio is used to compare one quantity with another, some connected phrases are ‘to every’ or ‘for every’ or ‘as many as’, e.g. We can convert quite easily between fractions and percentages by remembering what percentages represent. real life distance and distance on a map. mixing paint or one quantity with another quantity, e.g. Ratio is a way of comparing quantities, parts of a single quantity, e.g. Emphasise scientific contexts where such proportions have real meaning.īased on the fact that 1/ 10 is 0.1 pupils may wrongly generalise that, for example, 1/ 6 is 0.6. Students may think that it is impossible to have more than 100% or a fraction greater than 1. But, to make sure they understand what they are doing and can generalise it may be useful to check they understand that the line in a fraction stands for divide. Students will have their own mental strategies, for example finding a quarter by halving and halving again. For example finding 25% of a quantity is equivalent to finding a quarter so divide by 4. The representation used should be accurate and convenient given the context. Suggest that students are flexible in the way they choose which representation to use and also in the way they work using mental, written or calculator strategies. For example when rearranging an equation student often make the mistake of wanting to convert fractions to decimals which makes the processes involved less transparent. Encourage students to move between the different representations and discuss what makes a particular representation more appropriate in a given situation. In many cases students see these different representations as unrelated and the connections are not made. ![]() Percentages are fractions where the denominator is 100. We write decimal fractions with a decimal point. ![]() So 1/2 can be interpreted as a number on the number line between 0 and 1 and also as an operator divide by 2.ĭecimals can also be described as fractions where the denominator is a power of 10. Pupils need to be confident and fluent with fractions as numbers on a number line as well as operators. The ratio p : q corresponds to the fraction p/ q Ratios are fractions which express how many times one number can be divided by another. It is important that students understand that ratios, fractions, decimals and percentages are all just ways of describing divisions of a whole number. Summarised below are some of the common challenges students may face and then there are some example activities and resources that you may wish to use. If they struggle with the numbers this can impact their understanding of the real thing that the number is representing. However, it can be easy to make assumptions about the confidence and fluency students have with number and this can become a barrier to their understanding. The use of number to quantify physical systems, processes and quantities runs across pretty much all of the three sciences and so the need to be confident with numbers and simple calculations is effectively a core skill in all subjects and most topics. For example, 142857/999999 becomes 1/7.Ratios, fractions, decimals and percentages If necessary, take the fraction to the lowest term.was multiplied by 100, so the denominator is 100 - 1 = 99. To determine the denominator (lower number), subtract 1 from the number you multiplied with.To determine the numerator (top number), subtract out the repeating portion of the decimal.is multiplied by 100 (10 to the power of 2) and we get 13.131313. Determine how many repeating decimals there are and then multiply the decimal by 10 n, where n is the number of repeating decimals. ![]() there are 2 repeating decimals (13 is repeating). A repeating decimal is one that has a sequence of numbers that continually repeat. Change a repeating decimal into a fraction. ![]()
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |