Answer:
<h2>30</h2>
Step-by-step explanation:
<h3>to understand the steps</h3><h3>you need to know about:</h3>
- system of linear equation
- word problems
- PEMDAS
first step
let's create the equation word problem
<h3>my mother's current age is four times the sum of the ages of my two sisters. After 5 years, my mother's age will be double the sum of the ages of my two sisters. What is the current age of my mother? (imaginary problem)</h3>
let's solve
let my mother's and sister's age be x and y respectively
according to the first condition,x=4y....(I)
according to the 2nd condition,x+5=2(y+5×2).....(ii)
so the system of linear equations is
x=4y
x+5=2(y+5×2)
gets from the second equation
x+5=2(y+10)
x+5=2y+20
4y+5=2y+20 (as x=4y)
2y=15
y=7.5
so the age of mother is
x=4.(7.5)
x=30
a number that can written as 40 + 5 will be 45
Answer:
1.)616 in
2.)260 ft
3.) 744 mm
Step-by-step explanation:
Answer:
Step-by-step explanation:
X - y = 2400/6 = 400 where x = speed of plane and y = speed of wind.
x + y = 2400/5 = 480 - flying with the wind
adding the 2 equations
2x = 880
x = 440
Speed of the plane with no wind = 440 mph
