Question

An aggregate blend is composed of 55% aggregate A (Sp. Gr. 2.631), 25% aggregate B (Sp. Gr. 2.331) and 20% sand (Sp. Gr. 2.609). The Sp. Gr. of the blend aggregate is most nearly:_______
a. 2.732
b. 2.545
c. 2.581
d. 2.614

Answer 1

Answer:

The right choice would be Option b (2.545).

Explanation:

The given values are:

The aggregate blend will be:

$W_A$ = 55%

$G_ A$ = 2.631

$W_ B$ = 25%

$G_B$ = 2.331

$W_C$ = 20%

$G_C$ = 2.609

Now,

On applying the formula, we get

⇒ $G_{BA}=\frac{W_A+W_B+W_C}{\frac{W_A}{G_A} +\frac{W_B}{G_B} +\frac{W_C}{G_C}}$

On substituting the values, we get

⇒          $=\frac{55+25+20}{\frac{55}{2.631} +\frac{25}{2.331} +\frac{20}{2.609}}$

⇒          $= \frac{100}{\frac{55}{2.631} +\frac{25}{2.331} +\frac{20}{2.609}}$

⇒          $=2.545$