Answer:
Step-by-step explanation:
EXAMPLE #1:
What number is 75% of 4? (or Find 75% of 4.)
The PERCENT always goes over 100.
(It's a part of the whole 100%.)
4 appears with the word of:
It's the WHOLE and goes on the bottom.
A proportion showing one fraction with PART as the numerator and 4 as the denominator equal to another fraction with 75 as the numerator and 100 as the denominator.
We're trying to find the missing PART (on the top).
In a proportion the cross-products are equal: So 4 times 75 is equal to 100 times the PART.
The missing PART equals 4 times 75 divided by 100.
(Multiply the two opposite corners with numbers; then divide by the other number.)
4 times 75 = 100 times the part
300 = 100 times the part
300/100 = 100/100 times the part
3 = the part
A proportion showing the denominator, 4, times the diagonally opposite 75; divided by 100.
Answer:
14.99 hours
Step-by-step explanation:
The formula for half-life is given as,
R/R' = 2ᵃ/ᵇ...................... Equation 1
Where R= Original mass of sodium-24, R' = mass of Sodium-24 after disintegration, a = Total time taken for sodium-24 to disintegrate, b = half-life of sodiun-24.
Given: R = 1 kg, R' = 0.0156 kg, a = 90 hours
Substitute into equation 1 and solve for b
1/(0.0156) = 2⁹⁰/ᵇ
Taking the log of both side
log[1/(0.0156)] = log(2⁹⁰/ᵇ)
log[1/(0.0156)] = 90/b(log2)
90/b = log[1/(0.0156)]/log2
90/b = 6.0023
b = 90/6.0023
b = 14.99 hours
b = 14.99 hours.
Hence the half-life of Sodium-24 is 14.99 hours
The answer is 33. This is because there are 3 colours and the probability that the spinner will land on each colour is 1/3 (one third). To work out the number of times it will land on blue you have to do the probability of it landing on blue (1/3) multiplied by the number of times spun (100) which gives approximately 33.
Answer: 5/3(a)^6
Step-by-step explanation:
<span>[ (1 / 36) - (1 / x²) ] / [ (1 / 6) + (1 / x) ]
[ (x² - 36) / 36x² ] / [ (x + 6) / 6x ]
</span>remember that<span>:
x² - 36 = (x + 6)(x - 6)
so
[ (x+6)(x-6) / 36x² ] / [ (x + 6) / 6x ]
[ (x+6)(x-6) / 36x² ] * [ 6x / (x + 6) ]
6x / 36x² = 1 / 6x
[ (x+6)(x-6) / 6x ] * [ 1 / (x+6) ] -------------------- > </span>(x - 6) / 6x<span>
The answer is </span>(x - 6) / 6x<span>
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