Question

The fineness modulus of fine aggregate is 2.78 and of coarse aggregate is 7.82 and the desired fineness modulus of mixed aggregate is 6.14 mixed with one part of coarse aggregate ?

• A. 55%
• B. 50%
• C. 45%
• D. 40%

Answer 1

The correct option is B 50%

$\frac{\text{Fine aggregate}\left(FA\right)}{\text{Coarse aggregate}\left(CA\right)}\text{ratio be}x$

$\text{so,}\frac{\text{Combined aggregate}}{\text{Coarse aggregate}\left(CA\right)}\text{ratio will be}(1+x)$

$(1+x)\times 6.14=1\times 7.82+x\times 2.78$

$=\frac{7.82-6.14}{6.14-2.78}=0.5or\left(50\%\right)$