When equal volumes of two substance are mixed, the specific gravity of the mixurie is 4. When equal weights of the same substance are mixed, the specific gravity of the mixture is 3. The soecufuc gravities of the two substance could be

Explanation

`rho = (rho_1 V_1 + p_2 V_2)/(V_1 + V_2)`
`4 = (rho_1 V+ rho_2V)/(V + V) = (rho_1 + rho_2)/(2)`…(i)
`rho= (m_1 + m_2)/(V_1 + V_2) = (m_1 + m_2)/((m_1)/(rho_1) + (m_2)/(rho_2)) = (m + m)/((m)/(rho_1) + (m)/(rho_2)) = (2 rho_1 rho_2)/(rho_1 + rho_2)`
`3 = (2 rho_1 rho_2)/(rho_1 + rho_2)`...(ii)
`3 = (2 rho_1 rho_2)/(2 xx 4) rArr rho_1 rho_2 = 12`....(iii)
`(rho_1 - rho)^2 = (rho_1 + rho_2)^2 - 4 rho_1 rho_2 = (8)^2 - 4 xx 12`
=`64 - 48 = 16`
`rho_1 - rho_2 = 4` ...(iv)
`rho_1 + rho_2 = 8` ...(v)
`rho_1= 6, rho_2 = 2`.