The balls need for the given question is 28.
Given-
Total required string is 70.
The length of the required string is 40 cm.
The length of the ball of string is 10 m.
Convert the length of ball in centimetre from meter. We know that one meter has hundredcentimetres. Thus ten meters is,
Hence the length of the ball of string is 1000 cm.
Now the string is cut thus we need two lengths of string. Therefore,
Two length of string is 80 cm.
Now this is the half times the lengths of the seventy. Thus,
For this 2800 cm string we need 1000 cm string balls are,
Hence, the balls need for the given question is 28.
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