Question

Plz help me with this math and also explain

Answer 1

Explanation:

[1]

• SI = $250
• Rate (R) = 12
  `\sf (1)/(2)` %
• Time (t) = 4 years

`\longrightarrow \tt { SI = (PRT)/(100) } \\`

`\longrightarrow \tt { 250 = \frac{P * 12\cfrac{1}{2} * 4}{100} } \\`

`\longrightarrow \tt { 250 = \frac{P * \cfrac{25}{2} * 4}{100} } \\`

`\longrightarrow \tt { 250 = (P * 25 * 2)/(100) } \\`

`\longrightarrow \tt { 250 = (P * 50)/(100) } \\`

`\longrightarrow \tt { 250 * 100 = P * 50} \\`

`\longrightarrow \tt { 25000 = P * 50} \\`

`\longrightarrow \tt { (25000)/(50) = P } \\`

`\longrightarrow \underline{\boxed{ \green{ \tt { \$ \; 500 = P }}}} \\`

Therefore principal is $500.

__________________

[2]

• 2/7 of the balls are red.
• 3/5 of the balls are blue.
• Rest are yellow.
• Number of yellow balls = 36

Let the total number of balls be x.

→ Red balls + Blue balls + Yellow balls = Total number of balls

`\longrightarrow \tt{ (2)/(7)x + (3)/(5)x + 36 = x} \\`

`\longrightarrow \tt{ (10x + 21x + 1260)/(35) = x} \\`

`\longrightarrow \tt{ (31x + 1260)/(35) = x} \\`

`\longrightarrow \tt{ 31x + 1260= 35x} \\`

`\longrightarrow \tt{ 1260= 35x-31x} \\`

`\longrightarrow \tt{ 1260= 4x} \\`

`\longrightarrow \tt{ (1260 )/(4)= x} \\`

`\longrightarrow \underline{\boxed{ \tt { 315 = x }}} \\`

Total number of balls is 315.

A/Q,

3/5 of the balls are blue.

`\longrightarrow \tt{ Balls_((Blue)) =(3 )/(5)x} \\`

`\longrightarrow \tt{ Balls_((Blue)) =(3 )/(5)(315)} \\`

`\longrightarrow \tt{ Balls_((Blue)) = 3(63)} \\`

`\longrightarrow \underline{\boxed{ \green {\tt { Balls_((Blue)) = 189 }}}} \\`