Write an expression that can be used to find 4 x 275 using mental math and properties of numbers.
1 answer:
You might be interested in
Answer:
4
Step-by-step explanation:
Given
x + ← substitute x = 2 +
= 2 + +
Rationalise the denominator of the fraction by multiplying the numerator/ denominator by the conjugate of the denominator.
The conjugate of 2 + is 2 -
, thus
= 2 + +
= 2 + +
= 2 + + 2 -
= 4
Answer: 15meter is 25% of 60m
15m is 500% of 3m
15m is 50% of 30m
15m is 1% of 1.5km.
Step-by-step explanation:
Given: 15m is what percentage of 60m; 3m; 30m; 1.5km
To find: Find the percentage.
Formula used: 1 kilometer=1000meter.
Explanation:
Let X percentage of 60m =15meter
So, X% of 60m =15m
= 15m
Multiply both side by 100.
60X = 1500m
On dividing both side by 60
X = 25%
Let X percentage of 3m =15meter
So, X% of 3m =15m
= 15m
Multiply both side by 100.
3X = 1500m
On dividing both side by 3
X = 500%
Let X percentage of 30m =15meter
So, X% of 30m =15m
= 15m
Multiply both side by 100.
30X = 1500m
On dividing both side by 30
X = 50%
Let X percentage of 1.5km =15meter
Convert kilometer into meter by above formula (1.5km=1500meter)
So, X% of 1500m =15m
= 15m
Multiply both side by 100.
1500X = 1500m
On dividing both side by 1500
X = 1%
Therefore , 15meter is 25% of 60m
15m is 500% of 3m
15m is 50% of 30m
15m is 1% of 1.5km.