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5 votes
The length of a piece of string, L, is

40 cm when rounded to the nearest 10
centimetres. Brandon has written the
inequality below to show the lower
and upper bounds of L.
a) Give an example of a possible
length for the string that shows that
Brandon's inequality is incorrect.
b) Work out the correct inequality.
35 cm L < 44 cm

User Itodd
by
7.7k points

1 Answer

5 votes

Final answer:

Brandon's inequality for the length of the string is incorrect because it does not include all possible values that round to 40 cm.

The corrected inequality should be 35 cm ≤ L < 45 cm, and a length such as 43.5 cm would show that Brandon's original inequality is incorrect.

Step-by-step explanation:

The question pertains to the rounding of measurements and calculating the correct upper and lower bounds for the length of a string that has been rounded to the nearest 10 centimeters.

Brandon has written an incorrect inequality for the possible real length of the string (L) as 35 cm L < 44 cm.

To correct this, we need to consider what numbers would round to 40 cm.

Since we are rounding to the nearest 10 cm, any number from 35 cm up to but not including 45 cm would round down to 40 cm.

Thus, the correct inequality should be 35 cm ≤ L < 45 cm.

An example of a possible length that shows Brandon's inequality is incorrect could be 43.5 cm, as it does not satisfy Brandon's upper bound, but it would still round to 40 cm, which indicates the inequality should be 35 cm ≤ L < 45 cm instead.

User Tim Ryan
by
8.2k points