SAT Randomized Questions - 4 Full Math Practice Tests - Answers and Detailed Explanations at the END

To find \( f(0) \), substitute \( 0 \) for \( x \): \( f(0) = 180(0.3)^0 \). Since \( (0.3)^0 = 1 \), the expression becomes \( 180 imes 1 = 180 \).

Since the function decreases by 30%, it retains 70% of its value at each step. Thus, the multiplier for the decay is 0.70. Therefore, the correct equation is \( f(x) = 100(0.70)^x \).

The two equations are actually multiples of each other. Dividing the second equation by 2 yields \( 3x + 5y = 25 \). Thus, both lines coincide, which means they intersect at infinitely many points.

Only \( (3, 3) \) is a solution that satisfies both equations.

Using the quadratic formula, \(x = \frac{10 \pm \sqrt{100 - 8}}{2} = 5 \pm \sqrt{23}\). So, the solution can be written as \(5 + \sqrt{23}\) and the correct value of \(k\) is 23.

To find the doubling time, set \( h(t) = 2 \cdot h(0) \) and solve for \( t \): \( 45,000 \cdot (1.04)^{t/200} = 90,000 \). Use logarithms to solve for \( t \) and convert to hours.

The vertex of the function \( f(x) = \frac{1}{6}(x - 10)^2 + 4 \) occurs at \( (10, 4) \). This represents the minimum height of the basketball. The vertex form of a quadratic function, \( a(x - h)^2 + k \), indicates the vertex as \( (h, k) \). Since \( h = 10 \) and \( k = 4 \), the minimum height is 4 feet above the court.

Using the quadratic formula, \(x = \frac{12 \pm \sqrt{144 - 44}}{2} = 6 \pm \sqrt{25}\). So, the solution can be written as \(6 + \sqrt{25}\) and the correct value of \(k\) is 25.

Calculate the slope using the two points and find the equation of the line. Substitute \(x = m - 4\) to find the y-intercept \(b = 45\).

Since \( f(3) = 1024 \), substitute into \( f(x) = 8 \cdot d^x \): \( 8 \cdot d^3 = 1024 \Rightarrow d^3 = 128 \Rightarrow d = 4 \). Now find \( f(-2) \): \( f(-2) = 8 \cdot 4^{-2} = 8 \cdot \frac{1}{16} = 0.5 \).

The spill rate is 6 ounces per second. Over 30 seconds (half a minute), the volume spilled is 6 * 30 = 180 ounces.

Plug in the slope \( m = -2 \) and point \( (3, 7) \) into the point-slope formula to find the equation \( y = -2x + 13 \).

The two lines are parallel because their slopes are equal. Dividing the first equation by 2 yields \( 3.5x + y = 7.5 \). Since this differs from the second equation, the lines are parallel and do not intersect.

The half-life is 3 years, so the remaining quantity after \( x \) minutes is \( Q = 5 \cdot \left(\frac{1}{2}\right)^{\frac{x}{3 \cdot 365 \cdot 24 \cdot 60}} \).

In the function k(x) = -8x + 64, the y-intercept (where x = 0) represents the initial amount of concrete the worker had before building any foundations. When x = 0, k(0) = 64, indicating that the worker started with 64 cubic feet of concrete.

First, find the measure of angle Q in radians: \( \frac{5\pi}{6} + \frac{\pi}{4} = \frac{14\pi}{12} = \frac{7\pi}{6} \). Then, convert to degrees by multiplying by \( \frac{180}{\pi} \): \( \frac{7\pi}{6} \cdot \frac{180}{\pi} = 210 \) degrees.

Since the side lengths of square M are 15 times those of square N, the area of square M is \( 15^2 = 225 \) times the area of square N. Therefore, \( k = 225 \).

To cover the walls twice, double the total area \(w\) to get \(2w\). Since each gallon covers 300 square feet, divide \(2w\) by 300 to get \(P = \frac{w}{150}\).

Calculate percentages: Candidate X received \( \frac{350}{800} = 0.4375 \), or 43.75%. Candidate Y received \( \frac{450}{800} = 0.5625 \), or 56.25%. If 5,600 people vote, Candidate X would receive \( 0.4375 \times 5600 = 2450 \) votes, and Candidate Y \( 0.5625 \times 5600 = 3150 \) votes. The difference is \( 3150 - 2450 = 700 \) votes.

Let the number of small candles be represented by \( x \), and the number of large candles by \( y \). The total number of candles is at least 200, so we have the inequality:

\( x + y geq 200 \).

The budget constraint is that the total cost must not exceed $2,200. Therefore, we have the equation:

\( 4.90x + 11.60y leq 2,200 \).

We want to maximize the number of large candles, \( y \). First, solve for \( x \) in terms of \( y \) using the inequality:

\( x = 200 - y \).

Substitute this into the budget constraint:

\( 4.90(200 - y) + 11.60y leq 2,200 \)

Simplify:

\( 980 - 4.90y + 11.60y leq 2,200 \)

Combine like terms:

\( 980 + 6.70y leq 2,200 \)

Subtract 980 from both sides:

\( 6.70y leq 1,220 \)

Solve for \( y \):

\( y leq rac{1,220}{6.70} approx 182.09 \)

Since the number of candles must be an integer, the maximum number of large candles is 182.

The population doubles every 30 minutes, so it doubles twice per hour. After \( x \) hours, the population grows by a factor of \( 2^{2x} \).

Since triangles \( \triangle ABC \) and \( \triangle DEF \) are congruent, angle \( C \) corresponds to angle \( F \). Therefore, angle \( F \) must be 55°.

Since \(g(x) = f(x+2) = 8(5)^{x+2} = 8 \cdot 25 \cdot (5)^x = 200(5)^x\), the correct answer is g(x) = 200(5)^x.

Factor out the greatest common factor, \(5x\), from the expression: \(5x(x^2 + 7x + 12)\). Then factor \(x^2 + 7x + 12\) as \((x + 3)(x + 4)\). The smallest possible value of \(b\) is 3.

Substitute \( (-1, 3) \) into both inequalities. Both inequalities are satisfied.

To cover the walls twice, double the total area \(w\) to get \(2w\). Since each gallon covers 150 square feet, divide \(2w\) by 150 to get the equation \(P = \frac{w}{75}\).

To have no real solution, the discriminant of \(x(q x - 64) + 20 = 0\) must be negative. Solving gives \(\)q^2 < 16[/latex], so the smallest integer for [latex]q[/latex] is 4.

The lines have the same slope but different intercepts, indicating that they are parallel and do not intersect at any point.

Given \(\frac{m}{n} = 3\), rewrite as \(m = 3n\). Substitute into \(\frac{18m}{pn} = 3\) to get \(\frac{18(3n)}{pn} = 3\). Simplify to \(\frac{54n}{pn} = 3\), then cancel \(n\) to find \(p = 18\).

Substitute \( (2, 2) \) into both inequalities. Both inequalities are satisfied.

In the equation 3𝑠 + 50𝑡 = 8,000, the coefficient 3 corresponds to the trail, meaning 𝑠 represents the total number of streetlights per kilometer along the trail.

With \( h(4) = 810 \), substitute into \( h(x) = 10 \cdot c^x \): \( 10 \cdot c^4 = 810 \Rightarrow c^4 = 81 \Rightarrow c = 3 \). Now find \( h(-1) \): \( h(-1) = 10 \cdot 3^{-1} = 10 \cdot \frac{1}{3} = \frac{10}{3} \).

The leakage rate is 5 gallons per hour. Over one day (24 hours), the volume leaked is 5 * 24 = 120 gallons. Converting to pints (1 gallon = 8 pints), the answer is 960 pints.

Factor out the greatest common factor, \(4x\), from the expression: \(4x(x^2 + 8x + 24)\). Then factor \(x^2 + 8x + 24\) as \((x + 4)(x + 6)\). The smallest possible value of \(b\) is 4.

To find \( a \), set \( q(x) = 0 \): \( -7x + 21 = 0 Rightarrow x = 3 \), so \( a = 3 \). For \( b \), evaluate \( q(0) = 21 \). Thus, \( a + b = 3 + 21 = 24 \).

With \(p(x) = 0.75x\), the function decreases linearly as \(x\) increases, representing a consistent reduction in value. Hence, the answer is 'Decreasing Linear.'

Start by setting up the equation: \( 32,000 = 4,000(2)^{3r} \). Divide both sides by 4,000 to obtain \( 8 = (2)^{3r} \). Taking the logarithm base 2 of both sides yields \( 3 = 3r \). Therefore, \( r = 1 \).

To find the surface area, find the side length first. The volume of the cube is \( V = s^3 \). Given \( V = 729 \), \( s = \sqrt[3]{729} = 9 \). The surface area formula is \( 6s^2 \). Therefore, the surface area is \( 6(9)^2 = 486 \) square units.

Multiplying the first equation by -2 results in \( -2x + 8y = -6 \), which matches the second equation. Thus, the lines are the same, intersecting at infinitely many points.

To find \( a \), set \( g(x) = 0 \) and solve: \( -2x + 10 = 0 Rightarrow x = 5 \), so \( a = 5 \). For the y-intercept \( b \), set \( x = 0 \): \( g(0) = 10 \). Therefore, \( a + b = 5 + 10 = 15 \).

Only \( (2, 6) \) satisfies both equations.

Calculate the percentages: Candidate A received \( \frac{600}{1000} = 0.6 \), or 60%. Candidate B received \( \frac{400}{1000} = 0.4 \), or 40%. If 10,000 people vote, Candidate A is expected to receive \( 0.6 \times 10000 = 6000 \) votes, and Candidate B \( 0.4 \times 10000 = 4000 \) votes. The difference is \( 6000 - 4000 = 2000 \) votes.

The change in degrees Fahrenheit is determined by multiplying the temperature increase in kelvins by \( \frac{9}{5} \), since the \( x \) term in the function is being multiplied by this factor. Therefore, the increase in Fahrenheit temperature is \( \frac{9}{5} \times 3.00 = 5.40 \).

The system has no solution when the slopes are the same but the lines have different intercepts. Solving this condition gives n = 45.