Consider a data consisting of 10 observations x₁, x₂, …, x₁₀, whose mean is 5 and variance is 7. If the mean and the variance of the first 8 observations x₁, x₂, …, x₈ are 4 and 3.5, respectively, and x₉ < x₁₀, then the value of 3x₉ + 2x₁₀ is ___________.