The length of a chain is given as 16900 cm correct to the nearest 100 cm. What is the lower bound for the length of the chain?

16800 is the lower bound, it would have started with 16850 to be able to be rounded upwards to 16900 initially.

Step-by-step explanation:

Reasons are we only round up or down up 50 on the last value.

We cannot assume it has a lower value to begin with less than 50.

The degrees on a triangle add up to 180.

(x) + (x-7) + (3x+12) = 180 ; Just shwoing what i'm doing.

x + x-7 + 3x + 12 = 180

5x + 5 = 180 ; x + x + 3x = 5x , 12 - 7 = 5

5x = 175 ; Subtract 5 from 180

x = 35 ; 175/5 = 35

P: x - 7 = 35 - 7 = 28

Q: 3 (x) + 12 = 3 (35) + 12 = 105 + 12 = 117

R: x = 35