Maths MC

The answer is C

We use three examples in 0.8448<0.8452
they are 0.8449, 0.8450, 0.8451
When correct to 1 sig.figure, 0.8449 will be 0.8 but not 0.9
So A is wrong

When correct to 2 sig. figure, 0.8449 will be 0.84 but not 0.85
So B is wrong

When correct to 4 sig. figure, 0.8449 will be 0.8449 but not 0.8450
So D is wrong

When correct to 3 sig. figure, 0.8449 will be 0.845 , 0.8450 will be 0.845 and 0.8451 will be 0.845
So C is the answer

C.a=0.845
0.8448<0.845<0.8452

C,0.8448<0.845<0.8452

The answer is C.
A is wrong because if a = 0.8449, a = 0.8 (1 sig fig)
B is wrong because if a = 0.8449, a = 0.84 ( 2 sig fig)
D is wrong because if a = 0.8451, a = 0.8451 (4 sig fig)

個答案係 C

2007-11-17 23:10:47 補充：
你諗下：當 a = 0.8449 - 0.8451 是但一個數

2007-11-17 23:11:02 補充：
就拎中間數 0.8450corr to 1 sig fig 既話係 0.8corr to 2 sig fig 既話係 0.85 但諗諗：0.8449 既 2 sig fig 係 0.844，咁就唔可能揀 option Bcorr to 4 sig fig 既話係 唔知 ，因為你唔會知道佢第五個數可唔可以進倒位corr to 3 sig fig 既話，你代 0.8449, 0.8450, 0.8451 都可以 suit 倒Thus, option C is CORRECT.