Answer:15/2
Step-by-step explanation:
Answer: The age of the twins is 10 years.
Step-by-step explanation:
Suppose the age of older sister be x
Let the age of twins sister be x-9, as they are born after 9 years.
Product of their ages be

Sum of their ages will be

According to question,

So, Age of older sister will be 19 years.
Age of the twins will be

Hence, the age of the twins is 10 years.
Answer:
Divide both sides by V
Step-by-step explanation:
The equation is not well written.
Mariko needs to solve the equation below for D. Here is the equation:
M = DV
For Mariko to get D, he needs to make D the subject of the formula by dividing both sides of the equation by the coefficient of D i.e V as shown;
Divide both sides by V
M/V = DV/V
V at the denominator will cancel out the V at the numerator to have:
M/V = D
Rearrange
D = M/V
Therefore, the statement which correctly describes the step he should take is:
Divide both sides by V. Option B is correct.
The formula to figure out the percentage increase or decrease is:
<span>(new - old) / old * 100% </span>
<span>new = 60 </span>
<span>old = 72 </span>
<span>(60 - 72) / 72 * 100% </span>
<span>-12 / 72 * 100% </span>
<span>= -1/6 * 100% </span>
<span>= -0.1666... * 100% </span>
<span>≈ -16.667% </span>
<span>Because it is negative, that's a decrease. </span>
<span>Answer: </span>
<span>A decrease of about 16.7%</span>