- 15/24 × 90/15 = ? Multiply the Common (Ordinary) Fractions, Online Calculator. Multiplication Operation Explained Step by Step

The numerators and the denominators of the fractions are multiplied separately

These fractions reduce each other:

They have numerators and denominators of equal values.


The fractions: 15/24 × 90/15 = 90/24

Rewrite the equivalent simplified operation:

- 15/24 × 90/15 =


- 90/24

Simplify the operation

Reduce (simplify) the fractions to their lowest terms equivalents:

  • A fully reduced (simplified) fraction is one with the smallest possible numerator and denominator, one that can no longer be reduced, and it is called an irreducible fraction.
  • * By reducing the values ​​of the numerators and denominators of fractions, subsequent calculations become easier to perform.
  • To reduce a fraction to the lowest terms equivalent divide its numerator and denominator by their greatest common factor, GCF.

  • To calculate the GCF, factor the numerator and denominator of the fraction into prime factors.
  • Then multiply all the common prime factors: if there are repeating prime factors we only take them once, and only the ones having the lowest exponents (the lowest powers).

The fraction: 90/24

The prime factorizations of the numerator and denominator:

90 = 2 × 32 × 5

24 = 23 × 3


GCF (90; 24) = 2 × 3 = 6


90/24 =

(90 ÷ 6)/(24 ÷ 6) =

15/4


Yet another method to reduce a fraction:

* To reduce a fraction without calculating the GCF: factor its numerator and denominator, then all the common prime factors are easily identified and crossed out.


90/24 =


(2 × 32 × 5)/(23 × 3) =


((2 × 32 × 5) ÷ (2 × 3))/((23 × 3) ÷ (2 × 3)) =


(2 ÷ 2 × 32 ÷ 3 × 5)/(23 ÷ 2 × 3 ÷ 3) =


(1 × 3(2 - 1) × 5)/(2(3 - 1) × 1) =


(1 × 31 × 5)/(22 × 1) =


(1 × 3 × 5)/(22 × 1) =


15/4



Rewrite the equivalent simplified operation:

- 90/24 =


- 15/4

Rewrite the fraction

As a mixed number (also called a mixed fraction):

  • A mixed number: a whole number and a proper fraction, both having the same sign.
  • A proper fraction: the value of the numerator is smaller than the value of the denominator.
  • Divide the numerator by the denominator and write down the quotient and the remainder of the division, as shown below:

- 15 ÷ 4 = - 3 and the remainder = - 3 ⇒


- 15 = - 3 × 4 - 3 ⇒


- 15/4 =


( - 3 × 4 - 3)/4 =


( - 3 × 4)/4 - 3/4 =


- 3 - 3/4 =


- 3 3/4

As a decimal number:

Simply divide the numerator by the denominator, without a remainder, as shown below:


- 3 - 3/4 =


- 3 - 3 ÷ 4 =


- 3.75

As a percentage:

  • A percentage value p% is equal to the fraction: p/100, for any decimal number p. So, we need to change the form of the number calculated above, to show a denominator of 100.
  • To do that, multiply the number by the fraction 100/100.
  • The value of the fraction 100/100 = 1, so by multiplying the number by this fraction the result is not changing, only the form.

- 3.75 =


- 3.75 × 100/100 =


( - 3.75 × 100)/100 =


- 375/100 =


- 375%


The final answer:
written in four ways

As a negative improper fraction:
(the numerator >= the denominator)
- 15/24 × 90/15 = - 15/4

As a mixed number (also called a mixed fraction):
- 15/24 × 90/15 = - 3 3/4

As a decimal number:
- 15/24 × 90/15 = - 3.75

As a percentage:
- 15/24 × 90/15 = - 375%

How are the numbers being written on our website: comma ',' is used as a thousands separator; point '.' used as a decimal separator; numbers rounded off to max. 12 decimals (if the case). The set of the used symbols on our website: '/' the fraction bar; ÷ dividing; × multiplying; + plus (adding); - minus (subtracting); = equal; ≈ approximately equal.

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