Question

Solving Brain teaser using algebraic concept

a + a + a = 30

a + b + b = 20

b + 2c + 2c = 9

b + c . a = ?

Answer 1

Answer:

15

Step-by-step explanation:

Step 1. 5 + 1 . 10

Step 2. 5 + 10

15

Answer 2

Answer:

15

Step-by-step explanation:

To find:

• b + c * a

Method to find:

Let us start by finding the value of a.

a + a + a = 30   (Given)

⇒ 3a = 30

⇒ a = 30/3

⇒ a = 10  

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Now that we know the value of a, we can find the value of b.

a + b + b = 20     (Given)

⇒ a + 2b = 20

⇒ 10 + 2b = 20   (Subsituting values)

⇒ 2b = 20 - 10

⇒ 2b = 10

⇒ b = 10/2

⇒ b = 5

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Knowing the value of b, we can now find the value of c.

b + 2c + 2c = 9  (Given)

⇒ b + 4c = 9

⇒ 5 + 4c = 9    (Substituting values)

⇒ 4c = 9 - 5

⇒ 4c = 4

⇒ c = 4/4

⇒ c = 1

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To find b + c * a, we can substitute the values of a, b, and c into the expression.

⇒ 5 + 1 * 10

By BODMAS (Bracket, Order, Division, Multiplication, Addition, and Subtraction) we perform multiplication before addition.

⇒ 5 + 10

⇒ 15

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Hope it helps!