Comparing and ordering measurements
Compare and order lengths, mass, and capacity and record results using >, <, and =
What a learner can do afterwards
- Compare lengths, masses, volumes or capacities recorded in matching units using >, < and =
- Order lengths, masses or capacities and identify positions in the ordered list
- Use = and identify matching measurements when two measurements are the same
1 · Read
Compare the same attribute in matching units. In 36, the left digit means 3 tens (30); the right means 6 ones (6). A ten is 10 ones. Compare tens first, then ones if tens match. Use > for greater than and < for less than. The point faces the smaller number; the open side faces the larger: 4 cm < 9 cm.
Use = when measurements of the same attribute in matching units are equal. Two lengths of 14 cm match: 14 cm = 14 cm. Neither is longer. You can also find which records match a named measurement by checking both their number and unit.
To find the smallest measurement, compare all the numbers in the same unit. To order them, place the smallest first, then the next, then the largest. Jugs with capacities 3 cups, 6 cups and 9 cups go in that order. Use equal-sized, equally filled measuring cups.
Check a comparison by reading what its symbol says. Writing 2 cups > 7 cups says 2 is greater than 7. That does not match the numbers. Correct it to 2 cups < 7 cups. For an ordered list, check each neighbouring pair in turn.
When ordering named objects, keep each name with its measurement. Plants P, Q and R are 2 cm, 6 cm and 10 cm tall. From shortest to tallest, list P, Q, R. To fill a gap in an ordered list, choose a measurement between its neighbours.
Check attribute and unit: cm is length; g is mass. They cannot be ordered as two lengths. The third digit from the right counts hundreds, groups of 100. Compare hundreds, then tens, then ones. 200 has 2 hundreds; 80 has none, so 200 > 80. Find the largest by comparing all matching-unit values. Check a list for the first neighbouring pair that breaks its stated order.
Measure, compare the numbers, then write >, <, or = to show which is bigger, smaller, or the same.
Readings, questions and flashcards written for this topic. The referenced video is by Khan Academy.
2 · Watch
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Where this leads
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