Answer:
The Original length of uncut String is of 120 cm.
Explanation:
Let the length of original string be x.
Length of bracelet = 18 cm.
The necklace uses 50% of the string
Hence length of necklace will be equal to 50% of the string.
Length of necklace =

The anklet is 60% shorter than the necklace.
Length of anklet will be equal to difference of Length of necklace and 60% of the Length of necklace.
Length of anklet =

The bracelet needs 25% less string than the anklet.
Length of bracelet will be equal to difference of Length of anklet and 25% of the Length of anklet.
Length of bracelet =

But Length of Bracelet = 18 cm

Hence Total original Length of Uncut String is 120 cm.