The mystery number, represented by the expression 1.5 < c < 2 is 1.6
1.6 = 16/10 = 8/5
1.7 = 17/10
1.8 = 18/10 = 9/5
1.9 = 19/10
1÷8/5
= 1 × 5/8
= 5/8
= 0.625
1 ÷ 17/10
= 10/17
= 0.58823529411764
1 ÷ 9/5
= 5/9
= 0.55555555555555
1÷19/10
= 10/19
= 0.52631578947368
Learn more about decimals:
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