To answer this question you have to create a system of equations. The first equation will be that Devi's money (x) equals her brother's money (y), or x = y. The next equation would be that (3/5)x + (7/10)y = 78. You than can substitute x in for y because x = y. The equation would know be (3/5)x + (7/10)x = 78. You then combine the like terms to create an equation of (13/10)x = 78. Then, multiply both sides by 10 / 13 in order to isolate x. This will create the equation x = 60. This means that Devi and her brother each had 60 dollars. You then find out how much they spent and add it together. You can do so with the equation (2/5)x + (3/10)y = z, with z being total money spent. You substitute 60 in for x and for y then solve. When you solve you see that 24 + 18 = z, or that z equals 42. In other words, they spent 42 dollars altogether.
Answer:
The area of the associated sector is
Step-by-step explanation:
step 1
Find the radius of the circle
we know that
The circumference of a circle is equal to

we have

substitute and solve for r


step 2
Find the area of the circle
we know that
The area of the circle is equal to

we have

substitute

step 3
Find the area of the associated sector
we know that
subtends the complete circle of area 
so
by proportion
Find the area of a sector with a central angle of 

The expression which is equivalent to the given expression as in the task content is; 1.5 raised to the fifteenth power divided by 0.7 raised to the twelfth power.
<h3>What is the expression which is equivalent to the given expression?</h3>
According to the task content, it follows that the expression given is;
(1.5⁵/0.7⁴)³
= 1.5^(3×5) /0.7^(4×3)
= 1.5¹⁵/0.7¹².
Hence, the expression which is equivalent is; 1.5 raised to the fifteenth power divided by 0.7 raised to the twelfth power.
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Answer:
Step-by-step explanation: