Can someone help me for this question ?? Please

Let cost of Emma's phone = x

Given that cost of Sophie's phone = 640

Then ratio of their phones cost will be x:640 or x/640

Given that ratio of their phones cost is 7:8 or 7/8

So both ratios will be equal.

x=560

So the new ratio of the cost of their phones will be 560:640

Now we have to find about how much should the prices of their phones decrease in order to have a ratio of 9:11.

So let that decreased amount is k then we will get equation :

11(560-k)=9(640-k)

6160-11k=5760-9k

6160-5760=11k-9k

400=2k

200=k

Hence final answer is prices of their phones should decrease by 200 in order to have a ratio of 9:11.

To find the length of the missing side, you can use the Pythagorean Theorem, which you can only use for right triangles.

Pythagorean Theorem:  a² + b² = c²

[ c is the hypotenuse or the longest side of the triangle, and a and b are the other sides, I think it doesn't matter which side ]

Plug in what you know:

b = 8

c = 14

a² + b² = c²

a² + (8)² = (14)²

a² + 64 = 196       Subtract 64 on both sides

a² = 132       Square root both sides to get "a" by itself

a = inches

If you need to simplify more, you need to find two numbers that multiply to = 132 where one of them can be square rooted, to do so you can list the greatest common factors of 132

132: 1, 2, 3, 4, 6, 11, 12, 22, 33, 44, 66, 132

The only number that can be square rooted is 4, so you can do:

Answer:

4.200

Step-by-step explanation:

Change the divisor 0.9 to a whole number by moving the decimal point 1 places to the right. Then move the decimal point in the dividend the same, 1 places to the right.

We then have the equations:

37.8 ÷ 9 = 4.200

and therefore:

3.78 ÷ 0.9 = 4.200

Both calculated to 3 decimal places.

Final answer:

The division of 3.78 by 0.9 equals 4.2 after rounding to the nearest tenth. The given problem is an arithmetic division question typically encountered in mathematics. The keyword 3.78 is the number being divided by 0.9.

Explanation:

The division question posed: 3.78 divided by 0.9, is a simple arithmetic problem. To solve, we will perform the division calculation directly. First, we divide 3.78 (the dividend) by 0.9 (the divisor). This yields a quotient of approximately 4.2. Thus, 3.78 divided by 0.9 equals 4.2 when rounded to the nearest tenth. This division problem would be typically encountered in arithmetic, a branch of mathematics that deals with numbers and numerical computation.

Learn more about Arithmetic Division here:

brainly.com/question/32066115

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