Solve the formula for P P given r = − 5 r=-5 , t = 1.5 t=1.5 , and A = 21 A=21 . A = P ( 1 + r t ) A=P\left(1+rt\right)

For this problem, we need to solve the formula for P given the value for r, t, and a. So to get started, we're going to identify our known and unknown quantities. Here we know r is negative five, we know t is 1.5, and we know a is 21. But what we don't know is p. So our second step is to plug in our known quantities and then solve for the unknown. So we know a is 21, and that's gonna be equal to p, our unknown, times one plus r, we know is negative five, times t, we know is 1.5. Next, we need to simplify. So negative five times 1.5 is negative 7.5, And one minuteus negative 7.5 or one plus negative 7.5 is negative 6.5. And then isolating p, we'll divide both sides by negative 6.5. And we get p is equal to about 3.23. And that is our final answer.

3. Solving Word Problems

Formulas

Beginning Algebra

3. Solving Word Problems

Formulas

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Multiple Choice

Solve the formula for $P$ given $r = - 5$ , $t equals 1.5$ , and $A equals 21$ .
$A = P (1 + r t)$

$P=19.5$

$P=12.0$

$P=22.7$

$P=19.4$

Verified step by step guidance

Start with the given formula: $A = P \left(1 + r t\right)$.

To solve for $P$, isolate it by dividing both sides of the equation by the quantity $\left(1 + r t\right)$, giving: $P = \frac{A}{1 + r t}$.

Substitute the given values into the formula: $A = 21$, $r = -5$, and $t = 1.5$, so the expression becomes $P = \frac{21}{1 + (-5)(1.5)}$.

Calculate the value inside the parentheses in the denominator: multiply $r$ and $t$ first, then add 1.

Finally, divide $A$ by the result from step 4 to find the value of $P$.

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Struggling with Beginning Algebra?

Solve the formula for PP given r=−5r=-5, t=1.5t=1.5, and A=21A=21.A=P(1+rt)A=P\(\left\)(1+rt\(\right\))

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Solve the formula for $P$ given $r = - 5$ , $t equals 1.5$ , and $A equals 21$ .
$A = P (1 + r t)$