Question

2.8х(-3.9)-79.15:15.23

Answer 1

2.8  × (-3.9)  - 79.15 ÷ 15.23= - 16    4454/38075

1)2.8 × (-3.9) =-10.92

2) 79.15÷15.23 =7915/100  ×  100/1523 =  
=7915/1523 = 5  300/1523

3) -10.92   -  5  300/1523 =  - 10  92/100  -   5  300/1523 =
= -10   140116/152300    -  5    30000/152300=
= -(10+5) -   170116/152300 = - 15   - 42529/38075=
= -15 -  1   4454/38075 =  -16   4454/38075

Answer 2

To calculate the expression 2.8 × (-3.9) - 79.15 ÷ 15.23, we need to follow the order of operations (PEMDAS/BODMAS), which stands for Parentheses/Brackets, Exponents/Orders, Multiplication/Division, and Addition/Subtraction.

Let's break down the expression step by step:

1. 2.8 × (-3.9) = -10.92 (multiply 2.8 by -3.9)

2. 79.15 ÷ 15.23 = 5.193810075886356 (divide 79.15 by 15.23)

Now we can substitute these values back into the expression:

-10.92 - 5.193810075886356 = -16.113810075886356

Therefore, the result of the expression 2.8 × (-3.9) - 79.15 ÷ 15.23 is approximately -16.113810075886356.