Join 60,000+ competitive exam aspirants
The question stem appears to be missing. Based on the options provided, this may be a numerical calculation problem.
6.94
6.98
6.99
6.96
6.98
Use the algebraic identity a2тИТb2=(aтИТb)(a+b) in the numerator where a=4.33 and b=2.65. Notice that aтИТb=4.33тИТ2.65=1.68, which directly cancels the denominator.
Expression:1.684.33├Ч4.33тИТ2.65├Ч2.65тАЛ
a2тИТb2=(aтИТb)(a+b)
Use the algebraic identity a2тИТb2=(aтИТb)(a+b) in the numerator where a=4.33 and b=2.65. Notice that aтИТb=4.33тИТ2.65=1.68, which directly cancels the denominator.
Multiplying decimals manually without noticing the algebraic pattern, which leads to heavy calculation errors and wasted time.
Step 1: Identify the algebraic identity
The numerator has the form a2тИТb2 where a=4.33 and b=2.65. We apply the difference of squares identity: a2тИТb2=(aтИТb)(a+b)
4.332тИТ2.652=(4.33тИТ2.65)(4.33+2.65)
Step 2: Substitute and simplify the expression
Substitute the factored form into the given expression: 1.68(4.33тИТ2.65)(4.33+2.65)тАЛ
1.681.68├Ч(4.33+2.65)тАЛ
Step 3: Cancel common terms
Since 4.33тИТ2.65=1.68, the term 1.68 in the numerator cancels out with the denominator 1.68.
4.33+2.65
Step 4: Perform final addition
Add the remaining numbers: 4.33+2.65=6.98
6.98
B is correct because simplifying the expression using the identity a2тИТb2=(aтИТb)(a+b) yields 4.33+2.65=6.98.
Recognizing standard algebraic identities (a2тИТb2, (a+b)2) in numerical calculations saves valuable time in quantitative aptitude tests.