Answer
1) 7.750
2) 7.7500
Explanation
Equivalent decimals are decimals that are equal in magnitude or value.
A decimal number can have different decimal numbers but maintain the value. The zeros on the right hand side of the decimals are not significant and they do not change the value of the decimal.
For example, 1.5 = 1.50 = 1.500 = 1.500000
For the question above the two equivalent decimals to 7.75 are;
7.750 and 7.7500
