Because if you multiply 2 different irrational numbers (like the following)
You will get an irrational answer.
BUT
if you multiply the same square root (which are both irrational, you get a rational number)
Answer:
A) 0.265
B) 0.0265
C) 0.837
D) 0.0837
E) 0.00265
F) 0.00837
Step-by-step explanation:
We are given;
√7 = 2.65 and √70 = 8.37
A) √0.07 can be rewritten as;
√(7 × 1/100)
Let's deal with the digits in the bracket.
Square root of 100 is 10. Thus;
√(7 × 1/100) = (1/10)√7 = (1/10) × 2.65 = 0.265
B) √0.0007
Rewrite to get;
√(7 × 1/10000)
Square root of 1/10000 is 1/100
Thus;
√(7 × 1/10000) = (1/100)√7 = (1/100) × 2.65 = 0.0265
C) √0.7
Like above;
√0.7 = √(70 × (1/100))
>> (1/10)√70 = (1/10) × 8.37 = 0.837
D) √0.007
Like above;
Rewrite to get;
√(70 × 1/10000)
Square root of 1/10000 is 1/100
Thus;
√(70 × 1/10000) = (1/100)√70 = (1/100) × 8.37 = 0.0837
E) √0.000007
Rewritten to;
√(7 × (1/1000000))
√(1/1000000) = 1/1000
Thus; √(7 × (1/1000000)) = 1/1000 × √7 = 1/1000 × 2.65 = 0.00265
F)√0.00007
Rewritten to;
√(70 × (1/1000000))
√(1/1000000) = 1/1000
Thus; √(70 × (1/1000000)) = 1/1000 × √70 = 1/1000 × 8.37 = 0.00837
Lets write the problem info into an equation and solve step by step:
7(1/3 + 4/5)
the minimum common multiple of 3 and 5 is 15, so we multiply and divide the fractions by a proper number to convert them to be divided by 15 so is easier to add them:
<span>(1/3)(5/5) = (1*5)/(3*5) = 5/15
(4/5)(3/3) = (4*3)/(5*3) = 12/15
</span>so we substitute in the original equation:
7(1/3 + 4/5<span>)
</span>= 7(5/15 + 12/15<span>)
= 7(17/15)
= (7*17)/15
= 119/15</span>
Answer:
320 pesos
Step-by-step explanation:
Un 20% de descuento en formato decimal es 0.20. La totalidad de la bicicleta es representada como 100% o 1 y nosotros queremos saber el precio despues del descuento que seria
100% - 20% = 80% o 0.80
Ahora simplemente multiplicamos este decimal por el valor original de la bicicleta para saber el precio descontado...
400 * 0.80 = 320 pesos
