Find the upper bound for the following length: A) 18.7cm correct to 1 decimal place.
B) 58.37cm correct to 2 decimal places.

Please help.

Part A

Let's say we measure a board length and we measure 18.639 cm. Now let's say we round to the nearest tenth. That would lead to 18.6 cm. The question is "What is the largest value we can measure such that we round to the nearest tenth to get 18.7 cm?"

Well we could measure 18.7 cm exactly, but there are values we could measure that are larger to round to that value. We could measure 18.71 or 18.72, etc etc all the way up to 18.74; once we get to 18.75, it will round to 18.8

So this means that the largest we can measure is 18.74 and it is the upper bound we're after.

Part B

We use the same idea as part A, but now we're extending out one more decimal place.

We could measure 58.37 cm exactly or we could measure 58.371 or we could do 58.372, etc until we arrive at 58.374

By the time we get to 58.375, it will round to 58.38 and that's not what we're after. So the highest we can go is 58.374 cm

i think it is everything has to equal 180 so, if i correct 4=c. 6=d. 8=a. 7=b. and the last question would be c. because they are parallel lines and they are congruent.

step-by-step explanation:

the reason everything has to equal to 180 is because that is how it works. i'm guessing that is its rule. 4 and 8 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 6 and 7 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 60+60 is 180. so, now you have your answer

example 2 – simplify: step 1: completely factor both the numerators and denominators of all fractions. step 2: change the division sign to a multiplication sign and flip (or reciprocate) the fraction after the division sign; essential you need to multiply by the reciprocal. step 3 : cancel or reduce the fractions.