Simplify the following expression:
0.7+0.4
0.7
2
+(0.4+0.2)(0.7)+(0.4×0.2)
- A0.9
- B0.7
- C0.3
- D0.4
Solution & Step-by-step Explanation
Let a=0.7 and b=0.4.
Notice that the given expression has a form resembling algebraic identities. Let's rewrite the numerator using a=0.7, b=0.4, and let c=0.2.
The numerator is:
a
2
+(b+c)a+bc=a
2
+ab+ac+bc=a(a+b)+c(a+b)=(a+b)(a+c)
Substituting the actual values back:
a=0.7
b=0.4
c=0.2
So, the numerator becomes:
(0.7+0.4)(0.7+0.2)=(1.1)(0.9)
The given expression is:
0.7+0.4
(0.7+0.4)(0.7+0.2)
Canceling out the common term (0.7+0.4) from both the numerator and denominator:
=0.7+0.2=0.9
Notice that the given expression has a form resembling algebraic identities. Let's rewrite the numerator using a=0.7, b=0.4, and let c=0.2.
The numerator is:
a
2
+(b+c)a+bc=a
2
+ab+ac+bc=a(a+b)+c(a+b)=(a+b)(a+c)
Substituting the actual values back:
a=0.7
b=0.4
c=0.2
So, the numerator becomes:
(0.7+0.4)(0.7+0.2)=(1.1)(0.9)
The given expression is:
0.7+0.4
(0.7+0.4)(0.7+0.2)
Canceling out the common term (0.7+0.4) from both the numerator and denominator:
=0.7+0.2=0.9