Zara used
17 of the thread to tie some presents. She threw away
611 of the remaining thread. As a result, she had 210 cm of the thread left. How much thread did Zara have at first? Give your answer in cm.
Fraction of the thread left after tying some presents
= 1 -
17=
67 Fraction of the remaining thread left after throwing away
= 1 -
611=
511
Fraction of the total thread left
=
67 ×
511=
3077
Length of the thread at first = 77 u
Length of the thread left = 30 u
30 u = 210
1 u = 210 ÷ 30 = 7
Length of the thread at first
= 77 u
= 77 x 7
= 539 cm
Answer(s): 539 cm