Lisa deposits $3000 in an account that pays 2% simple interest, and $4000 in a second account which has a higher interest rate but is more risky. What minimum interest rate must she get on the second account in order to earn at least $700 in interest for the year?

just set up the inequality. If the other account has x interest, then

3000(.02) + 4000(x) >= 700
60 + 4000x >= 700
4000x >= 640
x >= 0.16 = 16%

To find the minimum interest rate Lisa must get on the second account, we need to set up an equation.

Let's assume the interest rate on the second account is "R%".

The interest earned on the first account can be calculated using the simple interest formula: I1 = P1 * R1 * T

Where:
I1 = interest earned on the first account
P1 = principal amount deposited in the first account = $3000
R1 = interest rate on the first account = 2% = 0.02
T = time (in years) = 1 year

Substituting the values into the formula, we get:
I1 = $3000 * 0.02 * 1 = $60

Now, let's calculate the interest earned on the second account:
I2 = P2 * R * T

Where:
I2 = interest earned on the second account (should be at least $700)
P2 = principal amount deposited in the second account = $4000
R = interest rate on the second account (to be determined)
T = time (in years) = 1 year

Substituting the values into the formula, we get:
$700 = $4000 * R * 1
$700 = $4000R

Now, we can solve for R by dividing both sides of the equation by $4000:
$700 / $4000 = R
0.175 = R

Therefore, Lisa must get a minimum interest rate of 17.5% on the second account to earn at least $700 in interest for the year.