6.75 is a number in decimal form. However, you can convert it into two other equivalent decimal forms. One is 6.7500... with as many 0s as you like. Although equivalent as a number, the greater the number of 0s, the greater the implied precision of the number. For example, 6.75 is accurate to the nearest hundredths but 6.750 to the nearest thousandths and so on.Another equivalent form is 6.7499... recurring, where the 9s continue for ever.
3.45 to the nearest decimal place = 3.5
There is no such thing as the "nearest decimal place".
5.43 to the nearest decimal place = 5.4
To the nearest decimal it must be 6868000000.018 since this is exactly equal to the specified number and any other representation would be different - no matter how small the difference.
2.53 rounded to the nearest decimal place is 2.5 2.53 rounded to the nearest decimal place is 2.5
what is 6.29892178 to the nearest 1 decimal place
The "nearest decimal" is a meaningless phrase. 53.238 is a decimal, as is 53.2380 for example. If it means 53.238 rounded off to the nearest tenths, the answer is 53.2.