Solve: 4×sqrt(0.49) + 4² | Mixed Operations Expression

Question

4×0.49+42= 4\times\sqrt{0.49}+4^2=

Video Solution

Solution Steps

00:00 Solve
00:03 Let's break down 0.49 to 0.7 squared
00:10 The square root of any number squared cancels out the square
00:15 Always solve multiplication and division before addition and subtraction
00:22 Let's use vertical multiplication to calculate the product
00:30 Note that any number multiplied by 0 always equals 0
00:43 Pay attention to the position of the decimal point
00:48 Let's continue solving
00:52 And this is the solution to the question

Step-by-Step Solution

To solve the expression 4×0.49+42= 4\times\sqrt{0.49}+4^2 = , we will follow the order of operations, which prioritizes operations inside parentheses, exponents and roots, followed by multiplication and division, and finally addition and subtraction.

1. Calculate the Square Root:
The first step is to solve the square root part of the expression. 0.49 \sqrt{0.49} .
0.49 0.49 is a simple decimal number whose square root is 0.7 0.7 , because 0.7×0.7=0.49 0.7 \times 0.7 = 0.49 .
So,0.49=0.7 \sqrt{0.49} = 0.7 .

2. Multiply:
Next, we multiply the result of the square root by 4:
4×0.7=2.8 4 \times 0.7 = 2.8 .

3. Calculate the Power:
Evaluate 42 4^2 .
42=16 4^2 = 16 , because 4×4=16 4 \times 4 = 16 .

4. Addition:
Now, add the results from the previous steps:
2.8+16=18.8 2.8 + 16 = 18.8 .

The final result of the expression 4×0.49+42 4\times\sqrt{0.49}+4^2 is 18.8 \boxed{18.8} .

Answer

18.8