Mathematics
NULL
Medium
Question
Evaluate (0.9² − 0.8²) ÷ 1.7.
A
0.1
✓ Official correct answer
B
0.2
C
0.3
D
0.4
Community credibility
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A
0.1
No member explanations yet for this option.
B
0.2
No member explanations yet for this option.
C
0.3
No member explanations yet for this option.
D
0.4
No member explanations yet for this option.
Explanation
0.81 − 0.64 = 0.17; 0.17 ÷ 1.7 = 0.1 (difference of squares: (0.9−0.8)(0.9+0.8)/1.7).