The measurements below were made on four different balances: i. 7.5 g
ii. 7.33 g
iii. 7.5201g
iv. 7.490

A student takes a reading from a balance where the display fluctuates between 7.51 g and 7.55 g. Which of the four balances above was used?

a. iv
b. iii
c. i
d. ii

d. ii.

Explanation:

Hello!

In this case, according to the displayed decimal placed by each balance, we can notice that:

i. Displays 1 decimal place.

ii. Displays 2 decimal places.

iii. Displays 4 decimal places.

iv. Displays 3 decimal places.

Thus, since the measured-out masses have two decimal places each, we infer that the used balance was d. ii as it displays two decimal places.

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